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IMPORTANT: Our products are for racing and may NOT be street legal. Products in the website DON'T come directly from our store - - - - - - CONTACT US before visiting. We only sell to USA and Puerto Rico. Currently this website is only for information, call us to place an order.
CONTACT US before visiting to check availability. Products may not be street legal. We only sell to USA and Puerto Rico
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

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