Product Review
✔ Screw head style: button; screw drive style: hex socket , known as internal hex drives
✔ Head diameter: 5.5mm/0.22"; head height: 1.6mm /0.06"; thread size: 3 mm; thread pitch: 0.5mm
✔ 10.9 alloy steel, hardness: HRC 32-39, tensile strength: 1040 N/mm²
✔ Rust proof: black oxide finish covered with anti-rust oil
✔ Easy to Store: These screws come in an easy-use storage case
Item----------Thread Length------Total Length
M3 x 20mm--------20 mm--------21.6mm
M3 x 25mm--------25 mm--------26.6mm
M3 x 30mm--------30 mm--------31.6mm
M3 x 35mm--------35 mm--------36.6mm
M3 x 40mm--------40 mm--------41.6mm
Package Contains:
M3 x 20mm------25Pcs
M3 x 25mm------25Pcs
M3 x 30mm------25Pcs
M3 x 35mm------25Pcs
M3 x 40mm------25Pcs
Total : 125 Pcs
About Hex Socket Drives:
 Hex Socket drives, also known as Internal Hex drives, have a hexagonal hole in the center that requires an Allen key, also known as a hex key or Allen wrench
About Button Head:
 Button head is similar to standard pan head screws but have a curved top