RAM Mount Handlebar U-Bolt Base Short Arm w/1/4" -20 Threaded Stud f/ Cameras [RAM-B-149ZA-C1U]RAM Handlebar Rail Mount with Zinc Coated U Bolt Base, Short Double Socket Arm & Round Base Adapter that Contains a 1 4" 20 Thread for Cameras Part #: RAM B 149ZA C1U The RAM zinc coated u bolt rail base consists of the 1" diameter ball and socket system with RAM Universal 1 4" 20 thread centered on a 2. 5" diameter plate. This mount is designed to be a universal mounting solution for both still and moving cameras. The base has a 1. 0" diameter rubber