... -4, diameter=0-400mm, quality can reach GB 4 The gears: Tooth (Z)Modul(M)Diameter(Φ)Normal Press Angle(a)DescriptionQuality ... 's requirment.Pinion gear, Spiral gear, Large gear,GB7, GB 6, GB 5, GB4Note: 1.The gears material can be 40Cr, 45 ... , carbonization,quench and temper, High and medium frequency etc. Steel gears for sliding doors