All Baldor Dodge V-drive sheaves are manufactured to ISO 9002 quality standards with precision machining that meets or exceeds joint RMA/MPTA industry standards for smooth operation and extended belt life. This provides low economical costs per hp transmitted due to shock load and vibration isolation creating clean, quiet operation. Dodge Multiple Groove Sheave, Type A Block, Taper-Lock Bore Type, 5.15 in Outside Dia, 4.78 in (A)/5.16 in (B) Pitch Diameter, 6 Grooves, 4-3/4 in Face Width, 1615 Bushing, For Use With: A and B Cross Section Classical Belt, Gray Iron Isolates vibration, cushions shock loadsMinor misalignment capabilityDrive ratios of 6:1 or more possibleLow maintenanceNo lubrication requiredEfficiency of 93% is typical