BIGBearing: The Pulley Bearing Takes a lot of abuse and is often the first thing to fail. We use a Larger Pulley Bearing for a much longer life. We designed our Billet Pulley with a snapring making the bearing replaceable. High Torque Coil: This OEM Upgrade is 120ftlbs of Torque (OEM Torque is 95 ftlbs). Higher Torque Means this Clutch holds Strong Even in the Toughest Cuts. Tough Billet Pulleys: Billet Pulleys Reduce Belt Wear and Maintain Perfect Blade Speed. Our Billet Pulley Design uses a Snap Ring and Allows for Bearing Replacement. Fits Freedom Z SZL52-24KT, GT1-CH-03L, GT1CH03L, SZL36-18FR, SZL36H-18F, SZL-36H-18FR, SZL48-18FR, SZL-36H-20KT, SZL-42H-21FR, SZL-42H-22KT, SZL48-21FR, SZL48-22KT, SZL48H-21FR, SZL52-21FR, SZL52-23FR, SZL52-24KT, SZL52H-23FR, SZL61-26KT, SZL61H-24FR, SZL-52H-23FR, SZL-52H-24KT, SZL61H-24FR, SZL-61H-24FR, SZL-61H-26KT, Fits: Liberty Z SFZ48-18FR, SFZ48-21FR, SFZ48-22KT SFZ48H-24KT, SFZ-48H-24K, SFZ52-24KT, SFZ52H-26KT, SFZ-52H-26KT, SFZ48-18FR Electric Deck Blade Power Take Off Clutch HD Clutch es are designed at HD Clutch and Assembled in the USA. Higher Torque: 110 ft-lbs (OEM is 95 ft-lbs). We add a few more windings to our coils to provide the maximum gripping strength to prevent damaging micro-slipping during tough cutting conditions. The HD Switch BIGBearing design addresses the #1 reason Clutch es fail with a larger tougher pulley bearing. Machined Billet Pulleys: It is easy to damage formed pulley and damage (even a small stone nick) damages the belt with every rotation. With our Billet Pulley design, we include a snap ring so the bearing is replaceable, making this Clutch rebuildable. Clutch es all run very hot; we use a composite material instead of plastic to allow the heat to dissipate much faster. This makes the HD Clutch run much cooler; extending the bearing and Clutch life. HD Clutch wrote the Bearing specifications to include Premium C3 Rated Bearings and high temperature rated synthetic grease to combat heat. Less Heat = Extended Life.