The TB Wood's BK521 4.95" Light-Duty Arm FHP Sheave with 1" Bore, 1 Groove, Cast Iron is engineered to provide efficient power transmission in light-duty applications. Designed for use with A (4L) or B (5L) cross-section V-belts, this sheave ensures optimal performance and reliability. Its cast iron construction offers durability and resistance to wear, making it suitable for various industrial settings. The finished bore accommodates a 1" shaft, and the keyway size is 1/4" x 1/8", facilitating secure mounting and alignment. With a face width of 0.875" and an overall length of 1-5/16", the BK521 sheave is compatible with TB Wood's Sure-Grip‚ QD-type bushings, allowing for easy installation and maintenance. This sheave is ideal for applications requiring efficient and economical power transmission solutions.