Universal Fit for Leaf Spring Applications: 9/16" thread size with 10" length and 3.125" inside width fits a wide range of leaf spring axle mounting applications - perfect for replacing worn factory u-bolts or custom suspension builds on trucks and trailers. Semi-Round Large Radius U-Bolt Kit with Hardware: Includes 4 semi-round u-bolts plus nuts and washers for a complete installation, giving you everything needed to secure both sides of your axle in one package. Heavy-Duty Steel for Maximum Clamping Strength: High-strength steel construction won't bend, crack, or fail under load - provides secure, reliable axle-to-spring mounting for your suspension system. Protective Finish: Black E-coating protects against rust from salt, mud, and moisture so your u-bolts stay strong and corrosion-free through tough weather and off-road abuse. Ideal for Suspension Lifts, Axle Swaps, and Maintenance: Perfect for lift kit installations, suspension repairs, or custom axle builds - these semi-round u-bolts deliver the secure clamping force your leaf springs demand.