This kit includes six (6) 9/16" x 3" “wet” shackle bolts (with grease zerks) and six matching locknuts – enough hardware for one single‑axle trailer (typically 4 bolts for spring-to-hanger connections, plus 2 spares or for equalizer setup). These bolts are a direct upgrade for standard dry shackle bolts, allowing you to grease the pivot points to reduce wear, prevent squeaking, and extend the life of your leaf spring suspension. Designed to fit common 1‑3/4" wide trailer leaf springs used on axle ratings from 2,000 lb up to 7,000 lb (including 3.5K, 5.2K, 6K, and 7K). Each bolt is drilled lengthwise with a grease zerk on the head, so lubricant reaches the bushing directly. Perfect for utility trailers, boat trailers, cargo trailers, and small RVs. Replace old, worn bolts during spring replacement or suspension maintenance.