Light Duty Fractional Horsepower (FHP) Sheaves are accurately machined from cast gray iron for strength and durability. They are statically balanced, and powder coated (painted) with a smooth attractive finish. BK sheaves are designed for use "B" belts, "4L" belts, as well as "A" belts & "5L" belts. They are common in many belt driven industrial power transmission applications, and most often utilized in HVAC equipment.