Features: 1. Product material: high quality cast steel, hardened by heat treatment (hrc45-52) 2. Product features: hardened and thickened, no slip and no tooth collapse, strong and durable Specification: Type:M/UM Material:Alloy Steel Wrench Shape:ER11/ER16/ER20/ER25/ER32 Color:Red&Black Note: Please allow 1-3mm errors due to manual measurement. Item color displayed in photos may be showing slightly different on your computer monitor since monitors are not calibrated same. Package Including: 1pc ER Spanner.