Walker 21521 Quiet-Flow Stainless Steel Muffler 100% structural stainless steel construction 3X the life expectancy vs. typical aluminized mufflers 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