BORLA 140785 Cat-Back™ System SILV./ SIERRA 1500 '19-'21 6.2L V8 AT 2+4WD CC SB EC STB (147"WB) 4DR 2.75" S-TYPE TRUE DUAL DDescription BORLA 140785 Cat Back System SILV. SIERRA 1500 '19 '21 6. 2L V8 AT 2+4WD CC SB EC STB (147"WB) 4DR 2. 75" S TYPE TRUE DUAL D This Cat Back system is designed for factory split rear exit vehicles, except ZR2 and AT4X models. It features a 2. 5" diameter inlet into 2. 75" pipes and a true dual design, which requires cutting the original equipment Y pipe. The system delivers the S Type sound level with no drone inside the vehicle. The muffler