Improves airflow up to 176 Percent. 4-inch constant-diameter cat-back system nearly triples flow. Straight-through muffler. 5-inch tip optional. Fully compatible with factory warranty. Monster Performance and Modest Price. Banks' new Monster Sport Exhaust is one cool cat-back system! And its low price? That's way cool. The system slashes backpressure, increases exhaust flow, improves fuel economy and delivers extra power to your rear wheels. Exhaust tip optional. 4 inch constant-diameter cat-back exhaust system. Virtually eliminates backpressure and nearly triples flow! Lowers exhaust gas temps. Straight-through Monster Muffler delivers a commanding exhaust note. Stainless Steel. Easy install. 5 inch rolled-edge polished tip is optional. Fully compatible with the Chevy/GMC factory warranty. 5-Year Limited Warranty.