Khrome Werks KW202895 3" HP-Plus Slash Cut Slip-On Mufflers Black for Sportster 14-21Description for Khrome Werks Black 3 in. HP Plus Slip On Mufflers 202895 Patented steel construction baffle now features more high temperature fiberglass packing, provides significant gains in horsepower and torque and exhibits a distinctive, throaty sound Use all factory mounting hardware OEM heat shields may be retained Sold in pairs U. S. patent 5,173,576 NOTE: ECM units on fuel injected models need to be recalibrated if used with free flowing air