RAM 1.5" Tough-Ball with 1/2"-20 X .50" Threaded Stud

Features: 1.5" diameter rubber ball with a 1/2"-20 X .5" stainless steel male threaded post Rubber ball fits RAM 1.5" ball (C size) compatible socket arms Designed for strength and durability Holds up to 4 lbs. with standard use or 3 lbs. with heavy-duty use Made in the USA   Thread Pitch: 1/2"-20 x .5" Brand: RAM Mounts Part number: RAP-379U-502050 Warranty: Manufacturer's lifetime warranty