On the off chance that I would need impact swivels doing work, I think I would just like to buy the universal joint that I can use any socket on it. So, what do you guys think about these two joints?
http://www.matcotools.com/catalog/product/BUP2BB/3-8-DRIVE-IMPACT-UNIVERSAL-JOINT/
http://www.matcotools.com/catalog/product/CUP2BC/1-2-DRIVE-IMPACT-UNIVERSAL-JOINT/
The 1/2" one says "ball" for the locking mechanism, so what is it suppose to mean? And I'm not sure what the 3/8" one is.
http://www.matcotools.com/catalog/product/BUP2BB/3-8-DRIVE-IMPACT-UNIVERSAL-JOINT/
http://www.matcotools.com/catalog/product/CUP2BC/1-2-DRIVE-IMPACT-UNIVERSAL-JOINT/
The 1/2" one says "ball" for the locking mechanism, so what is it suppose to mean? And I'm not sure what the 3/8" one is.

