The TB Wood's BK4078 is a precision-engineered light-duty web sheave designed to accommodate A (4L) and B (5L) cross-section V-belts. With a 7/8" finished bore diameter and a 3.95" outside diameter, this sheave ensures optimal belt engagement and efficient power transmission. Constructed from high-quality cast iron, it offers durability and resistance to wear, making it suitable for various industrial applications. The single groove design facilitates smooth belt operation, while the finished bore allows for easy installation and maintenance. This sheave is compatible with TB Wood's Sure-Grip QD-type bushings, providing a secure and reliable mounting solution. By integrating the BK4078 into your machinery, you can enhance operational efficiency and extend equipment lifespan.