Walker 21181 Quiet-Flow Stainless Steel Muffler Assembly OE-style louvered tube technology lowers noise level for premium OE-style sound compared to straight perf. tubes Precise OE-style routing &amp; hanger positions for quick &amp; easy installation Comprehensive internal drainage system for corrosion resistance OE-style domed heads help reduce radiated noise compared to flat heads Spun-locked heads to help prevent rupture