Solomark Dovetail Clamp with 2 Brass Screw with Pressure Shoe for Mounting Vixen/celestron Fits Dovetail Plates, Length:88mm Height:28mm For Mounting Vixen, Celestron, Synta and GRII/III Dovetail Plates 2 Brass Screws will tighten the dovetail Plates. Versatile with many brands model