Uxcell a15072400ux0080 Plastic Head Clamping Knob Jig M4 x 10mm Male Thread Product Name : Clamping Knob; Type : Screw On Head Diameter : 15mm / 0.6"; Thread Size : M4 x 10mm/0.162" x 0.4"(D*L) Total Height : 24mm /0.9"; Material : Metal, Plastic Color : Black; Weight : 39g Package Content : 10xClampingKnob