High quality plastic and rubber materials ensure durability The ball size is 25mm/1" of diameter compatible with RAM Mounts B Size Double Socket Arm and other brackets that fit this size ball One bracket work for Baofeng Yaesu Motorola Quansheng Retevis Cobra and other radios with back clip, the other bracket work for handheld mic with back clip Package Includes: 1*radio bracket adapter with 25mm ball 25mm 1" Ball Adapter