3.5" x 5.5" Half-Sheave Shear Reduction Block Pulley by CMI . This revolutionary half-sheave design creates a lighter block that attaches parallel to a cable, using less hardware. Stainless steel sideplates, 3" aluminum sheave, axle. Extra thick sideplates and multiple stainless rivets for maximum strength and protection. This top-grade product is expertly made in compliance with stringent industry standards to offer a fusion of a well-balanced design and high level of craftsmanship. Manufactured from industry-leading materials using up-to-date equipment, it ensures everlasting reliability and enduring value. This product is distinguished by total quality assurance, unsurpassed by anybody else.