DDY-64i 64mm Discal (circular) ClampVery versatile Jaw opening range of 37.25mm to 41.5mm will accommodate any Arca style plate from various makers including:Really right stuff (RRS), Wimberley, Jobu Design, Arca Swiss, Kirk Enterprises,Markins, etc. Can be used on virtually any head, tripod or monopod. Very versatile, you can mount it to any 3/8"-16 post or 1/4"-20 (using the included 1/4" bushing adapter) or you can remove your existing clamp and replace it using the 6mm hex screw provided.Will fit many brands of ball heads & including Arca-swiss, RRS etc.Especially well suited for Arca- Swiss P0.Diameter: 64mm.Length: 81mm. Height: 15.5mm. Weight: 80g.All metal construction, no rubber or plastic. Includes bubble level and the accessories pictured.