RAM Universal Wheelchair Ball Base (RAM-B-238-WCT) (sku 53763)This B size RAM diamond ball base features a universal hardware pack that accommodates the armrest and seat tracks on most major wheelchair brands, including Invacare, Permobil, and Quickie. Pair with a variety of compatible RAM double socket arms and device holders to build a custom mount to meet your specific needs. Hardware included (2) #10 32 T Nuts (2) #10 32 Flat Weld Nuts (2) #10 32 x 1 2" Machine Screws (2) M4 x 12mm Machine Screws (2)M4 x