Lightness, convenience, good toughness, no scratches on any material, and firmness and durability. Good material, high toughness, no damage to building materials. High standard, high precision, easy to use, thread is not easy to slip and deform. Butterfly shape, easy to , without hurting hands, easy to use. The service life of the butterfly nut is prolonged. colour:Black Material:Plastic + Metal size:8.5cm x 8.5cm x 3cm Package Contents: 10 x CNC Arcuate Press Plate Clamp 10 x T-Screw 10 x Butterfly Nut 10 x Circular Gasket Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.