The Starrett 435ME features reversible lock bolts, a scriber and a spirit level in both square head and protractor head. The double 180° protractor scale is direct reading. All the heads are finely machined cast iron with a traditional black wrinkle finish. The hardened steel, machine-divided blade is 300mm(12in), graduated: 1/2 mm and 32nds one side, mm and 64ths on the reverse.