Replace the small muffler behind the primary muffler in the Borla(r) S-Type system with Polyphonic Harmonizer 60680 to attain the ATAK(r) sound level (louder than S-Type). Borla(r) 'S Polyphonic Harmonizer Technology utilizes patented units that contain pipes of different diameters and lengths to create multiple exhaust notes that harmonize to deliver a clean, rich, full-bodied sound to the Borla(r) mufflers. The mufflers then enhance this sound to the character and volume appropriate for our Touring, S-Type and ATAK(r) systems. Built from premium T-304 stainless steel, superior to T-400 series (such as 409), to give you the absolute best in performance and durability. Ultra-smooth mandrel bends ensure maximum flow & power, and precision computer numerical control (CNC) manufacturing ensures an accurate fit. Best of all, Borla(r) stands behind every Polyphonic Harmonizer with a Million-Mile Warranty. Just what you'd expect from the world's most experienced (and most winning) exhaust brand.
Installation Instructions


This Part Fits:

Year	Make	Model	Submodel
2020-2021	Chevrolet	Silverado 1500	Custom Trail Boss
2019-2025	Chevrolet	Silverado 1500	High Country
2020-2025	Chevrolet	Silverado 1500	LT Trail Boss
2019-2025	Chevrolet	Silverado 1500	LTZ
2020-2025	Chevrolet	Silverado 1500	RST
2022-2025	Chevrolet	Silverado 1500	ZR2
2022	Chevrolet	Silverado 1500 LTD	Custom Trail Boss
2022	Chevrolet	Silverado 1500 LTD	High Country
2022	Chevrolet	Silverado 1500 LTD	LT Trail Boss
2022	Chevrolet	Silverado 1500 LTD	LTZ
2022	Chevrolet	Silverado 1500 LTD	RST
2019-2025	GMC	Sierra 1500	AT4
2024-2025	GMC	Sierra 1500	AT4X
2019-2025	GMC	Sierra 1500	Denali
2024-2025	GMC	Sierra 1500	Denali Ultimate
2019-2025	GMC	Sierra 1500	SLT
2022	GMC	Sierra 1500 Limited	AT4
2022	GMC	Sierra 1500 Limited	Denali
2022	GMC	Sierra 1500 Limited	SLT