Borla 22-23 Chevrolet Silverado 1500 ZR2 & AT4X 6.2L CC SB 147.5in WB S-Type True DualBorla 22 23 Chevrolet Silverado 1500 ZR2 & AT4X 6. 2L CC SB 147. 5in WB S Type True Dual This Cat Back(tm) system features the classic BORLA(r) S Type sound level and turn down tail pipes, and is unique in the industry. It features a "True Dual" design which requires cutting the factory Y Pipe. It was designed specifically for the Silverado 1500 ZR2 and Sierra 1500 AT4X and delivers great sound without any drone. Muffler contains an internal H Pipe