Gears sold as a single unit, match pair with module size to give a 2:1 ratio. Delrin Bevel Gears. Injection moulded acetal co-polymer bevel gears. Tensile strength 75N/mm ;sup>2 ;/sup> Hardness (Rockwell R) 110-120 Pitch angle 63° 26' (gear) 26° 34' (pinion) Face angle 65° 36' (gear) 30° 29' (pinion)