1Fitment: Heavy duty shackle kit fit for CRE3000, fit for Stock, and fit for Equaflex 3 1/8in shackle. The heavy duty shackle kit is an excellent upgrade for your running gear and the answer for wear and tear. 2Wide Application: The heavy duty shackle kit is available for both tandem and triple axle trailers and will fit units with upgraded suspension systems. 3Complete Shackle Upgrade Kit: The heavy duty kit includes shackle brackets, bronze bushings, greaseable bolts and nuts. 4Professional Design: Thicker shackles for added strength. Bronze bushings for more durability. Greasable bolts for less maintenance. 5Ideal Replacement: A direct replacement for worn shackles, works with an equalizer to give your trailer a smooth, quiet ride. Very nice upgrade.