WHY CHOOSE YOUXMOTO?Trailer springs made of strong steel plate, stable transmission.Extra rust-proof coating added to handle harsh environments.Design from professional factory , Improved performance.SIZE: 1750 lb Capacity Per Spring; For 3,500 lbs TrailersEye to Eye length: 25-1/4 inchFree open: 3 inchwidth of leaf: 1-3/4 inchLeaf Thickness 5/169/16 inch bushing dia, 2 Bushings Installed for Each Spring4 leavesReplace: For SW4B Package: 2 Trailer Leaf SpringsInclude 3,500lbs axle U-bolt kit for 2-3/8" dia round trailer axlesKit include: 4 x 5-1/2" long U bolts, U bolts dia. 1/2"; 2 x tie plates for 1-3/4" leaf springs; 8 x 1/2"-20 hex nuts. Include Complete single trailer axle hanger kit for 1-3/4" leaf springs.Kit include:2 x 3" tall hangers; 2 x 2.1" tall hangers; 4 x shackle straps (eye to eye 3.09"); 6 x 9/16"-18 x 3" long shackle bolts and locknuts.Warm Tips: If a leaf spring is cracked or broken, it should be replaced immediately. We recommend using a wire brush to remove debris and dirt caked on the spring to aid in visual inspection.