Stanley Proto J7121 1/2" Square Ext, 7/16" Hex

Work great and well built

works well

I use this regularly at work with a half inch drill and 15/16 socket. So I've broken quite a few 1/4" shank adapters. I don't think this one will ever break. I really like the 7/16" shank on this. The locking stud also is appreciated

Very solid base. Much better then expected. Only one I was able to find to prevent twisting of base on impact driver.

Good product

Works great! Not sure if it's over time or just the strength of the impact but mine have broken, 2 in the past year or so. I keep a backup just in case it breaks. Still beats paying the other prices.

Not sure how to write this so everyone can picture it in their head. But chucked it up into a 7.5 amp low rpm, high torque drill and screwed together 15 30lbs sub-barrels simultaneously, so basically it handled all the torque of spinning 450lbs of steel from 0 to 600 rpm then slamming to a hard stop when the threads made up. The 1/4 bits kept snapping for the same process, so if you have broken a 1/4 socket adapter I would definitely recommend this product.

I use this proto tool for Half inch sockets and a Hole auger tool. so I can use it on a Bruit Winder. For large Commercial garage door springs.