Variable Speed Pulleys - Precision Series #FZX-B4-2

Material: Glass reinforced nylon, with steel shafts and steel-clad flange for greater wear resistance. Speed range infinitely variable within standard ratio limits. Pulleys are shipped with a blue, heavy srength spring unless another srength spring is requested. For the FZX-B1 series, we recommend the heaviest blue spring be used if the pulley is to be run with 3/8 - inch width V-belt. Set screw supplied. *Close tolerance on Round Shaft *Molded Keyway *Precisely ground and Polished Shaft *Spring loaded and color coded to indicate spring pressure *Simple belt tensioning adjustments allows for speed changes from 2.25:1 up to 2.8:1