The Stanley 15mm High Grade CRV Steel Combination Spanner is a top quality spanner that is built to last. It is made of high grade CRV steel that is extremely durable and will withstand a lot of wear and tear. Introducing the Stanley combination spanner! This hand tool is made of high-quality chrome vanadium steel and is finished in a sleek matt black.� Anti-slip design on open end. Maxi-Drive system helps reduce fastener rounding.