I'm not sure who they are, but a lot of their items have the same number as WW Grainger.

http://www.zoro.com/i/G3248944/?category=5157

http://www.grainger.com/product/WESTWARD-Transmission-Jack-1ZKY3?s_pp=false&picUrl=//static.grainger.com/rp/s/is/image/Grainger/5ML73_AS01?$smthumb$

I also bought one of those from Zoro yesterday also. We use a heavier OTC jack for transmissions, but these lighter ones work well for installing SPL 250 Drive shafts. I bought the same part number over 10 years ago from WW Grainger, and we just flat wore it out. 30% off the Zoro price made it very attractive.