5-50PCS Hex Hexagon Socket Flat Head Screw 304 Stainless Steel DIN7991 Countersunk Allen Screw Bolt M2 M2.5 M3 M4 M5 M6 M8 M10 Feature: The flat head socket screws are bolts designed to fit inside a countersunk hole. A countersink is both the recessed hole and the tool to make the hole that allows compatible screws and bolts to screw in flush to a surface. Flat head screwss are mostly hidden when screwed in, because their heads are shaped to fit within the special holes. Specification: Product Name: hex socket flat head screw Material: 304 Stainless Steel (A2-70) Thread diameter: M2 (2mm) / M2.5 (2.5mm) / M3 (3mm) / M4 (4mm) / M5 (5mm) / M6 (6mm) / M8 (8mm) / M10 (10mm) Thread pitch: 0.4mm (M2) / 0.45mm (M2.5) / 0.5mm (M3) / 0.7mm (M4) / 0.8mm (M5) / 1mm (M6) / 1.25mm (M8) / 1.5mm (M10) Thread length: 3mm - 100mm Package Included: 5/10/20/50pcs x Hex socket flat head screw Note: Please allow minor error due to manual measurement. Thank you Item color displayed in photos may be showing slightly different on your computer monitor since monitors are not calibrated same.