Home » Internal Hard Drives and SSD

OWC Special Offer Available

$70.99 off *NOW* Get Parallels Desktop Pro Edition - Windows/Multi OS Compatibility software for Mac - Only $29.00 with select OWC SSDs, HDDs, Memory, External Storage, and Optical Drives! (Limit 3 rebates, 1 rebate per qualifying item)
Must purchase with: PPDPROSUB1Y-REB29

DIY Bundle

and Internal SSD Kit for 2011 21.5" iMacs

Mercury Electra SSD and SSD Bay Solution
Upgrade with Confidence!
The complete solution for your 2011 iMac
Configuration flexibility is yours when you add a second internal drive using the OWC SSD bay kit. Boost your storage capacity by adding additional storage, and enjoy near-instantaneous boot and app loading times thanks the performance of an OWC 6G SSD.
Fast and reliable solid-state storage
With incredible sustained data speeds, up to 100X greater data protection than enterprise class Hard Disk Drives, and RAISE technology for RAID like data protection and reliability, the OWC Mercury 6G SSD line delivers unbeatable performance, that's backed by an incredible OWC SSD Limited Warranty.
We are here to help
OWC's SSD bay kit comes backed by OWC's award-winning U.S.A. based technical support team which is readily available to assist you with your upgrade should you have any questions. If you are not fully confident of your ability to add an SSD to your 2011 21.5-inch iMac, you can choose to have OWC "Do It For You" via our Turnkey Upgrade Installation Program.

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.

2.0TB Mercury Electra 6G SSD Specifications:


Silicon Motion 2258 with 7% Over Provisioning
Form Factor
Standard 7mm 2.5"
SATA 6Gb/s, 3Gb/s & 1.5Gb/s supported, SATA 3.0 Compliant
Capacity 1
1920GB useable capacity
Total Flash Memory Components – 2048GB
128GB allocated to real-time data redundancy & error correction
RAID Support
SMART Attributes
Standard 2
Native Command Queuing
up to 32 commands
Manufacturer Model Number
RoHS Compliant


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


MTBF (Mean Time Between Failures)
TRIM Support
OS Dependent


Sequential Reads
(Compressible Data)
up to 530MB/s
Sequential Writes
(Compressible Data)
up to 494MB/s
Sequential Reads
(Incompressible Data)
up to 522MB/s
Sequential Writes
(Incompressible Data)
up to 311MB/s


2.1 W
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.

Manufacturer provided specifications for Other World Computing p/n K21IM11SE2TB UPC#: 812437025859


SSD Install Video

This product is compatible with... Learn how to find your Mac's model ID
iMac Intel
iMac (21.5-inch Late 2011)
(August 2011)
Model ID: iMac12,1
3.1GHz i3
iMac Intel
iMac (21.5-inch Mid 2011)
(May 2011)
Model ID: iMac12,1
2.5GHz i5 , 2.7GHz i5, 2.8GHz i7


  • (1) OWC Mercury Extreme Pro 6G SSD
  • (1) 18" SATA III 6Gbps data cable
  • (1) SSD Power Cable for 2011 21" iMac
  • (2) OWC 2-1/4" Suction Cup
  • (1) Torx T10 driver
  • (1) Torx T6 driver
  • (1) Phillips #2 driver
  • (1) Nylon Pry Tool (Spudger)
  • (1) iMac Adhesive tape set for SSD installation
  • (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.


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 on the OWC Mercury Electra 6G SSD

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 5 / 5 1 out of 1 (100%) reviewers would recommend this product
Verified Buyer
Reviewer: Josh12 Location: Josh12 Age: 35-44 Experience Level: Home User Owned Product: 1-3 months
Rating: 5/5 SSD add-in drive February 22, 2018 I don’t recommend this upgrade for the average user. I had no problems with it, since I work on cell phone and computer repairs daily.

I would recommend this item to a friend! This review is from DIY Kit for 2011 21.5" iMac's internal SSD bay: 500GB OWC Mercury Electra 6G SSD. Customer Videos:

Verified Buyer
Reviewer: SRProducciones Location: Acuna, MX. Age: 25-34 Experience Level: Home User Owned Product: less than a month
Rating: 5/5 Very excellent upgrade January 22, 2018 What can I say, its just amazing how you can speed up your Mac with just an SSD Drive. The Kit has all you need to do the installation, the instructional videos explains everything, just need to be patient in the process, I did mine in 2 hours but absolutly worths the time and the money, the customer attention excellent too

I would recommend this item to a friend! This review is from DIY Kit for 2011 21.5" iMac's internal SSD bay: 120GB OWC Mercury Electra 6G SSD.. Customer Videos:

DIY Bundle 2.0TB OWC 6G SSD and Internal SSD Kit for 2011 21.5" iMacs Mfr P/N: K21IM11SE2TB OWC SKU: OWCK21IM11SE2TB Complete DIY kit for adding an SSD to your 2011 21.5" iMac's internal SSD bay. 3 Year OWC Limited Warranty Ships: Same Day only $359.75
Add to CartOther World Computing K21IM11SE2TB In Stock, Click to Buy Now
Additional Capacities:
  • 120GB
    • Ships: Same Day
    • Only $64.98
    • Bundle Priced for $42.75
  • 250GB
    • Ships: Same Day
    • Only $87.98
    • Bundle Priced for $67.75
  • 500GB
    • Ships: Same Day
    • Only $127.98
    • Bundle Priced for $109.75
  • 1.0TB
    • Ships: Same Day
    • Only $199.98
    • Bundle Priced for $166.75
  • 2.0TB