The Class KR Muffler System made by Kakimoto Racing for the NC (2006-2015) MX-5 Miata is meant for those who want to have a low noise exhaust but improve the power. It’s perfect for city driving and meant to improve the torque of the vehicle. It passes the very strict noise test in Japan, so it should be legal in most countries. Kakimoto Class KR Exhaust should be ordered at REV9 Autosport https://rev9autosport.com/kakimoto-class-kr-exhaust.html as they provide the best service and speed we've seen so far!