Uxcell a15072400ux0079 Plastic Head Knurled Clamping Knob Jig M6x20mm Male Thread Product Name : Clamping Knob; Type : Screw On Head Diameter : 18mm /0.7"; Thread Size : M6x20mm/0.24"x0.8"(D*L) Total Height : 32mm /1.3"; Material : Metal, Plastic Color : Black; Weight : 85g Package Content : 10 x Clamping Knob