This 100mm ball fits our 100mm bowl (and most other manufacturer's 100mm bowl) for use on the Pegasus Carbon with a 100mm Bowl, Atlas 30 slider with a 100mm Bowl or the Ballare Dolly. The entire assembly is designed to be very low profile to allow use of a rig without interference below the rails. The ball allows you to mount any tripod head and attaches using the standard 3/8" thread. Any of Manfrotto's tripod heads for example, attach directly. It is computer machined from billet aluminum, lightened, then anodized for a lifetime of good looks. The tensioning knob is a work of art, and of course the threaded shaft is stainless steel for a corrosion proof assembly.