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DIY Bundle

250GB OWC 6G SSD
and HDD Kit for 21.5" iMac (2012 and later)

Mac / USB 3.0
Mercury SSD and iMac HDD Kit
Everything You Need!
The complete solution for your 2012 and later 21.5" iMac
Experience the extreme performance of an OWC SSD upgrade with this easy DIY SSD and hard drive replacement kit. Add an SSD to your hard drive equipped iMac to experience faster booting, near instant application launches and data transfer speeds up over 500 MB/s.
Fast and reliable solid-state storage
Delivering the latest in flash NAND and controller technology, utilizing SLC and 3D NAND for long-lasting, power-efficient performance, the OWC Mercury 6G SSD line offer a powerful combination of performance and reliability for demanding everyday computer users.
A True DIY upgrade
This comprehensive kit has all the tools you need to replace your factory HDD with a high performance SSD, bringing a complete diy upgrade within your reach. Includes drivers, glass removal suction cups, and screen adhesive so you can get the job done yourself. The included OWC Express 2.5" USB 3.0 enclosure offers maximum mobile data storage/backup potential with a sleek, totally bus powered design. Just add your iMac's factory 2.5" hard drive or SSD and take your digital life with you wherever you roam!


Please note, that before attempting to perform this installation, it is recommended you watch the associated instructional video in its entirety to determine your ability to perform this complex procedure. OWC assumes no responsibility for damage that may occur during the install.

Release Candidate (RC) firmware set

There are two kinds of firmware for SSDs Mass Production (MP) and Release Candidate (RC). Prior to an MP firmware release, there are beta firmware releases and an RC firmware release. Often, the RC is the same as the MP release, however there can be small changes and bug fixes made between the two. OWC has evaluated the RC for the 6Gb/s SandForce 2281 Processor and found it to be stable with no issues reported during our testing. However, as with any evolutionary product, issues may surface as different usages and configurations are employed and it is important to understand that there will be further updates and revisions.

Since no firmware update is currently offered for the OWC Mercury EXTREME Pro 6G SSD, no update page exists. To see the typical steps involved with a self performed field firmware update, please visit our 3Gb/s product update page at: http://eshop.macsales.com/Customized_Pages/Framework.cfm?page=sf_firmware.html

It is important to note that the current firmware update tool requires the use of Windows XP/Vista/7. OWC is currently working on a Mac OS based update tool, but we do not have an exact availability date.

250GB Mercury Electra 6G SSD Specifications:

Specifications

Controller
4-Ch
NAND
Tier 1 3D NAND
Form Factor
Standard 7mm 2.5"
Interface
SATA 6Gb/s, 3Gb/s & 1.5Gb/s supported, SATA 3.0 Compliant
Capacity 1
250GB useable capacity
RAID Support
Yes
SMART Attributes
Standard 2
Native Command Queuing
up to 32 commands
RoHS Compliant
Yes
Format

Physical

Height (max)
7mm (0.276″)
Width (max)
70.06mm (2.758″)
Length (max)
100.12mm (3.941″)
Weight
77 grams +/- 2 grams
0.170 lbs +/- 2.71 oz

Reliability

TRIM Support
OS Dependent

Performance

Sequential Reads
(Compressible Data)
up to 522MB/s
Sequential Writes
(Compressible Data)
up to 463MB/s
Sequential Reads
(Incompressible Data)
up to 506MB/s
Sequential Writes
(Incompressible Data)
up to 443MB/s
Random 4K Read
up to 90,000 IOPS
Random 4K Write
up to 60,000 IOPS

Power

Active
2.1 W
Idle
0.9 W

Environmental (Operating)

Temperature (°F)
32°F to 158°F
Temperature (°C)
0°C to 70°C

Environmental (Non-Operating)

Temperature (°F)
-40°F to 185°F
Temperature (°C)
-40°C to 85°C
  1. 1GB = 1,000,000,000 bytes. Total accessible capacity varies depending upon operating environment (typically 5-10% less). The actual total capacity will depend on your own defined file settings/preferences. 
  2. Temperature reporting is currently an unsupported feature because due to the operating characteristics of SSDs, it is highly unlikely one would ever exceed an OWC Mercury SSD's stated operating temperature ceiling of 158F/70C. However, we are looking into supporting this feature in the future via a firmware update. Firmware updates can be found here: http://eshop.macsales.com/tech_center/OWC/SSD.

Express Enclosure Specifications:

OWC Part Number

  • ES2.5BU3S

Software Requirements

  • OS
    • Mac OS 8.6 or later
    • OS X 10.2 or later
    • Windows 98 or later
  • Driver
    • Driver not required

Hardware Requirements

  • Minimum
    • Mac or PC featuring USB 1.1 interface
  • Recommended (Best Performance)
    • Mac or PC featuring USB 3.0 interface

Interface (Chipset)

  • (1) USB 3.0 (ASMedia ASM1053E)

Drives Supported

  • (1) 2.5" SATA 6Gb/s drives
    • SATA revision 3.0 (6Gb/s) compliant
    • Compatible with SATA revisions 2.0 (3Gb/s) and 1.0 (1.5Gb/s)

Power Supply

  • Bus Power via USB

Dimensions

  • Height: 0.6 in (1.5 cm)
  • Width: 3.1 in (7.9cm)
  • Length: 5.1 in (13.0 cm)

Weight

  • Without Drive: 2.0 oz (56 g)

Operating Environment

  • Dependent on mechanism installed
Manufacturer provided specifications for Other World Computing p/n K21IM12HE250 UPC#: 812437028706

Gallery

Install Video

Note:Mercury Electra 6G SSDs can only be installed in 21.5-inch iMac models that came with a factory-installed HDD or Fusion drive. Solid-State Drive (SSD) only machines can be upgraded with an Aura Pro X2 SSD (Late 2013 - Current) or Aura 6G SSD (Late 2012 - Early 2013).
iMac Intel
iMac w/Retina 4K display
(21.5-inch Early 2019)
(March 2019)
Model ID:iMac19,2
3.6GHz i3, 3.0GHz i5, 3.2GHz i7
iMac Intel
iMac w/Retina 4K display
(21.5-inch Mid 2017)
(June 2017)
Model ID:iMac18,2
3.0GHz i5, 3.4GHz i5, 3.6GHz i7
iMac Intel
iMac (21.5-inch Mid 2017)
(June 2017)
Model ID:iMac18,1
2.3GHz i5
iMac Intel
iMac w/ Retina 4K display (21.5-inch Late 2015)
(October 2015)
Model ID:iMac16,2
3.1GHz i5, 3.3GHz i7
iMac Intel
iMac (21.5-inch Late 2015)
(October 2015)
Model ID:iMac16,1
1.6GHz i5, 2.8GHz i5
iMac Intel
iMac (21.5-inch Mid 2014)
(June 2014)
Model ID: iMac14,4
1.4GHz i5
iMac Intel
iMac (21.5-inch Late 2013)
(September 2013)
Model ID: iMac14,3
2.9GHz i5 or 3.1GHz i7
iMac Intel
iMac (21.5-inch Late 2013)
(September 2013)
Model ID: iMac14,1
2.7GHz i5
iMac Intel
iMac (21.5-inch Early 2013)
(March 2013)
Model ID: iMac13,1
3.3GHz i3
iMac Intel
iMac (21.5-inch Late 2012)
(October 2012)
Model ID: iMac13,1
2.7GHz i5 , 2.9GHz i5, 3.1GHz i7

Includes

  • (1) OWC Mercury Extreme Pro 6G SSD
  • (1) OWC Express enclosure - silver
  • (2) OWC 2-1/4" Suction Cup
  • (1) Torx T10 driver
  • (1) 21.5" iMac Adhesive tape set for proper display resealing
  • (1) Nylon Pry Tool (Spudger)
  • (1) OWC Screen Removal Tool
  • (1) OWC Blue Microfiber Screen Cleaning Cloth

NOTE: This kit contains consumable and/or one time use components and therefore is non-refundable if opened. If you have any concerns about your ability to perform the upgrade, you can return the unopened kit for a refund.

Warranty

The best warranty is one you never have to use - but should the need occur - we're proud to provide a superior level of support and service coverage to our customers.

3 Year OWC SSD Limited Warranty

1 Year OWC Enclosure Limited Warranty

Even when not used, we understand the peace of mind afforded by a longer warranty period. OWC's industry leading coverage is a testament to our confidence in the reliability of the solutions that we offer. OWC solutions are engineered to demanding quality standards in order to deliver the most reliable, highest performance available on the market in each storage category.

Customer Ratings

Write a Review 4.8 / 5 16 out of 16 (100%) reviewers would recommend this product
1 2
Verified Buyer
Reviewer: GarSC Location: Santa Cruz, CA Age: 55-65 Experience Level: Home User Owned Product: 1-3 months
Rating: 5/5 Huge Performance Gain December 15, 2017 Upgrade me 2014 iMac’s 5400 HD to SSD and the memory to 16GB. Huge performance gain in booting, application launching, photo editing. The SSD installation wouldn’t be too bad, probably no more than 1/2 hour to 45 minutes. Replacing the memory is much more involved. The installation videos were great and made the whole process doable. Highly recommend this upgrade.

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 1.0TB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: ponticelli Location: Milan Age: 35-44 Experience Level: Home User Owned Product: less than a month
Rating: 5/5 Amazing solution December 14, 2017 I was a "old" customer of MacSales...and so I went to this page to upgrade my iMac 2013. The kit is simply amazing: it has everything you need to replace your disk, all the needed tools, a superb step by step video tutorial about how-to-do that. The only thing that was missing, was a guide - as step 0 - to prepare your disk in the external case with a new installation, so that when you install it, everything works great.

I would recommend this item to a friend! Customer Videos:

Verified Buyer
Reviewer: jlaage Location: Iowa Age: Over 65 Experience Level: Power User Owned Product: over 6 months
Rating: 5/5 Imac Upgrade to SSD October 29, 2017 I found my IMac to be slow at loading programs from disk. Swapping in the subject SSD kit made a huge improvement, sorry no benchmarks but subjectively. Swapping the system drive was more an arts and crafts project than the usual computer repair. The you tube video was an important part of the process. Extra hands and fingers are also useful. I found my wife's assistance invaluable in placing the adhesive strips to resecure the screen and in holding parts in place. This change made the computer behave much more like I had expected when purchased.

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 1.0TB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: MaxEnvoyPRO Location: Brazil Age: 45-54 Experience Level: Home User Owned Product: less than a month
Rating: 5/5 OWC Mercury Electra 6G SSD is Excellent June 14, 2017 So fast!!!

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 1.0TB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: MattHawaii Location: Hawaii
Rating: 5/5 Great support May 15, 2017 Everything you buy at OWC comes with great support. In this case it was website and video support. It must be expensive to have all those experience technical people on staff, but, for some reason, their prices are good. I consider OWC one of the miracles of retailing.

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 480GB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: ITrunner Location: Tucson, Arizona Age: 25-34 Experience Level: IT Professional Owned Product: 1-3 months
Rating: 5/5 Turned an old iMac from miserable to amazing! April 27, 2017 Used this kit to upgrade a coworkers Late 2013 iMac 14,1 with an old 5200 rpm HDD. The machine was miserably slow and really struggling with Mac OS Sierra.

The install video was super helpful and much easier than I expected. The whole install was done in 20 minutes.

The new drive has been performing amazingly for a few weeks (coworker is very happy).

No complaints. Can't recommend enough.

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 480GB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: billyork23
Rating: 5/5 Easy install - easy speed improvement March 27, 2017 I had an existing Time Machine backup so this upgrade was rather easy for me. I upgraded the RAM at the same time so the process - not including Time Machine restore - took less than 2 hours.

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 1.0TB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: deans2delhi
Rating: 4/5 deans February 21, 2017 Great quality will definitely buy again

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 480GB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: Krish Location: New Bombay, India Age: 25-34 Experience Level: Home User Owned Product: less than a month
Rating: 5/5 Easy Upgrade. February 15, 2017 I was scared initially to open up my new 4K iMac. But once I started I was surprised how easy it was and the entire process of swapping the hard drive to SSD was simple and was done in 20 mins. SSD makes a ton of difference to the system performance and would advise anyone to swap it if they bought a mechanical hdd equipped Mac.

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 240GB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: GeorgeKY Location: Somerset KY Age: 45-54 Experience Level: IT Professional Owned Product: less than a month
Rating: 5/5 iMac like a rocket now February 1, 2017 I wanted to take the time to come and write a review of my recent purchase and self installation of a SSD drive in my 21.5" late 2013 iMac. From the product selection process on OWC's website helping me locate my exact SSD to the shipping video replacement guide and former HD (1TB) content migration, all went fantastic. My wife was always complaining about the spinning beachball she would endure. This has been completely eliminated. The machine has become a pleasure to work on now. If you value your time, I highly recommend an upgrade from ordinary HD's to SSD. Thank you Other World Computing!

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 480GB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: jh27 Location: Surrey, BC Age: 45-54 Experience Level: Power User Owned Product: less than a month
Rating: 5/5 Everything needed for the job December 8, 2016 This package made it easy to switch out my HD. With the online instructional video, I had no problems. Everything went smooth and works like a dream.

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 1.0TB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: 4jwd Location: Roanoke Valley, Virginia Age: Over 65 Experience Level: Home User Owned Product: 1-3 months
Rating: 5/5 One Great SSD..! December 6, 2016 Adding the Mercury Electra 1.0 Tg. SSD was the best upgrade for my iMac. It has greatly enhanced the speed and response of the computer..!

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 1.0TB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: mrbilky Location: Philadelphia PA Age: 45-54 Experience Level: Power User Owned Product: over 6 months
Rating: 5/5 Excellent service, top notch instructions! December 4, 2016 My iMac became painfully slow boot up and getting the spinning ball of death all the time watched the video on this installation it was very intuitive and took the plunge my iMac is like new and very snappy - tripled my read/write speeds, don't be afraid of this upgrade very easy took 20 minutes and most of that was peeling off the old adhesive. Oh and don't panic if you misplace a strip or two of new adhesive the kit provides extras!

This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 480GB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: enplaned Location: Ithaca, NY Age: 45-54 Experience Level: Home User Owned Product: 1-3 months
Rating: 4/5 Worked like a charm September 6, 2016 Successfully upgraded HDD to an SSD in my parents' iMac, radically improving its speed/response. OWC made it do-able, if not exactly easy. Watched the videos many,many times, and took great care at all times and it all worked out. It is not for the faint of heart, but it was less of a big deal than I expected.

They will get another five years out of the iMac, I bet.

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 240GB OWC Mercury Electra 6G SSD.. Customer Videos:

Verified Buyer
Reviewer: Anonymous Location: Texas Age: Over 65 Experience Level: Home User Owned Product: 1-3 months
Rating: 5/5 Great SSD July 8, 2016 My factory installed hard drive began to fail on my iMac after only two years. After viewing the OWC video on replacing it, I decided to try to replace it. Everything worked as advertised and now I have an iMac that is working better than ever.

Having a 1Tb internal hard drive fail has caused me to keep all important files on an external drive and backup everything.

I would recommend this item to a friend! This review is from DIY Kit for 2012 or later 21.5" iMac's factory HDD: 240GB OWC Mercury Electra 6G SSD..

DIY Bundle 250GB
OWC 6G SSD
and HDD Kit for 21.5" iMac (2012 and later) Mfr P/N: K21IM12HE250 OWC SKU: OWCK21IM12HE250 Complete DIY kit for upgrading your late 2012 or later 21.5" iMac's hard drive 3 Year OWC Limited Warranty Ships: Same Day Only $114.86Bundle Priced for $84.75
Add to CartOther World Computing K21IM12HE250 In Stock, Click to Buy Now
Additional Capacities:
  • 120GB
    • Ships: Same Day
    • Only $148.78
    • Bundle Priced for $50.75
  • 250GB
  • 500GB
    • Ships: Same Day
    • Only $142.90
    • Bundle Priced for $119.75
  • 1.0TB
    • Ships: Same Day
    • Only $226.86
    • Bundle Priced for $181.75
  • 2.0TB
    • Ships: Same Day
    • Only $406.86
    • Bundle Priced for $366.86