Product Review

✔ Alloy steel, 10.9 Tensile strength
✔ Fully threaded; Machine Screw
✔ Meets/Exceeds: ISO7380
✔ Screw head style: Button; Screw drive style: Internal Hex, known as Hex-socket Drives
✔ These screws comes in an easy-use separated girds storage box

***Length Information***
---Item---------------Thread Length------------Total Length
M4 x20mm-----------20mm----------------------22mm
M4 x25mm-----------25mm----------------------27mm
M4 x30mm-----------30mm----------------------32mm
M4 x35mm-----------35mm----------------------37mm

***Package Quantity***
M4 x20mm-----------25Pcs
M4 x25mm-----------25Pcs
M4 x30mm-----------25Pcs
M4 x35mm-----------25Pcs
Total-----------------100Pcs

***About Internal Hex Drives***
Internal hex drives, also known as hex-socket drives, are similar to hex drives, but 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 screws are similar to standard pan head screws but have a curved top.