The EKLIND 15510 Metric Plain Hex Key is the ideal tool for working with fasteners. Made of alloy steel, this hex key has a black oxide finish that protects against corrosion. The plain handle allows you to apply pressure in any direction you want when turning or holding a fastener. This metric hex key is 5 mm in tip size and 3 5/64 in long with an arm length of 3 in. This hex key will give you the leverage you need to loosen or tighten fasteners, giving you the best performance possible.