11MM diameter is universally compatible with all cameras. 14MM diameter is compatible with the majority of cameras, but is not suggested with medium format cameras which have the shutter button next to the lens (ie. Hasselblad, Mamiya, and Rolleiflex).
REG THREAD compatible with majority of cameras having a threaded shutter button. (ie. Fuji, Leica, Canon 35mm Film, Nikon 35mm Film, Pentax 35mm Film)
FAT THREAD compatible with Leica M3. medium format Hasselblad, Rolleiflex, and Mamiya cameras.