I change batteries on various types of vehicles daily, bought a lot of tools and found this to be one of the best skinny sockets that protrudes 14mm to allow you to clear both terminal nuts without touching the top of the battery than when using other types where the thickness of the ratchet housing could create a clearance problem. On some vehicles like Lexus where the terminal nut is on a In hard-to-reach places, the 10mm ratchet side is very useful. I don't unscrew batteries with 5/16"β¦