This combination of the Boss Adapter and the 58mm Clamp will fit virtually any Manfrotto ball head and produce a head that is Arca compatible. Own a Manfrotto 484, 486, 488, 494, 496, 498, 054, 055 and 057 series ball head and wish to use AS (Arca-Swiss) compatible system? The Haoge Female to Male Boss Adapter and 58mm Clamp allows you to more easily replace the clamp on your Manfrotto ball head. Arca Swiss compatible quick release clamp. The Boss Adapter has a ridge on one side which fits in the groove on the underside of the quick release clamp, and a ridge on the other side which fits in the groove on the Manfrotto ball head. Hex key and mounting screw are included Please note: The Manfrotto Ballhead is not included and is showing for illustration only.