S&S Cycle GNX 4.5in. Slip-On Mufflers - Black with Tuxedo Black End Cap 550-0990Muffler bodies measure a full 4. 5in. OD Premium fit, finish, sound and power Unique louvered baffle delivers a more aggressive tone, even with stock head pipes S&S racing heritage styled end caps with a black tuxedo finish SAE J2825 Sound Level Complaint (with included dB reducer installed); dB reducer is removable Relieved for shocks up to 131 2in. length Sold in pairs Made in the U. S. A.