Martin 1VP34 3/4 VP Sheave, 3L/4L/5L or A/B Belt Section, 1 Groove, 3/4" Bore, Class 30 Gray Cast Iron, 3.15" OD, 7876 max rpm, 1.9-2.8" Pitch Diameter/2.0-3.0 Datum/2.3-3.2 Datum