HTP timing pulleys 3M 5M 8M 14M 20M XL L H XH XXH T205 T5 T10 T20 AT5 AT10 MATERIAL:HT250 or Aluminum All series of the timing pulleys XL-XXH ,3M-20M,T205-T20 and AT5-AT10.produced by ZZBC are adopted advanced production technology and of high quality. they are really the first choice of users. TIMING PULLEY