Spiral Cut Steel Bevel Gears Steel gears with cyclo-palloid toothing. Angle between axes is 90°. Steel is 42 Cr Mo 4 (induction hardened with ground hubs and bores) up to and including module 1.5. Module 2.0 and over is 16 Mn Cr 5, teeth hardened and lapped where indicated. NOTE: To achieve stated ratios select MATCHED pairs of gears. MATCHED gears have consecutive order codes with identical ratios and modules. To achieve 1:1 ratios order TWO of the same gear