The 300mm - 11-3/4" Combination Set with Square, Center and Reversible Protractor Head and Blade features a reversible lock bolt, scriber, spirit level in both square head and protractor head, direct reading double 180° protractor scale, hardened steel, photo-engraved blade. The combination set with square includes a cast iron head with black wrinkle finish. FEATURES: Reversible lock bolts, scriber, spirit level in both square head and protractor head. Direct reading double 180 Deg protractor scale. Hardened steel, machine divided blade. Regular Finish Blade. Cast Iron Heads with Black Wrinkle Finish.