This was made for a ThinkPad E440 but should fit the following models as well:

Thinkpad E430
Thinkpad Y480
Thinkpad E431
Thinkpad E435
Thinkpad E440
Thinkpad E445
Thinkpad E530
Thinkpad E531
Thinkpad E540
Lenovo G480
Lenovo Z580

I didn't want to fight with repeated prints to fit the battery release mechanism. I just addded holes to the plug and made the Jig to line up holes I could drill in the laptop case. In the end, the plug fitted snugly enough right off the printer that drilling holes wasn't neccessary.