Square Head Size (L*W):2.5 x 2.5mm / 0.1" x 0.1"(M3),3 x 3mm / 0.12" x 0.12"(M4), 4 x 4mm / 0.16" x 0.16"(M5) ,5 x 5mm(M6) ,4.8 x 4.8mm/ 0.19" x 0.19" (M8).
【Usage】Used for processing ordinary internal threads on nuts or other parts, tapping on machine tools.
【Package Included】5pcs Machine Screw Thread Metric Plug Tap