I.nternational standard Timing Belt Pulley 2.Most competitive on European market 3.3M ... 14M,T5,T10,MXL, XL, S3M,S5M... Steel Timing Belt PulleyPulley type:MXL,XL,L,H,XH,XXH,3M,5M ... black of oxidation,zincing,nickelage,anode.Machine:CNC engine lathe,milling machine,drilling machine,gear shaper,hobbing machine,grinder,testing ... oxidation):Pulley (Black of oxidation):Nylon Pulley: Steel Timing Belt Pulley