High performance header by Leg Motor Sport for the 1.5L ND (2016+) Mazda Miata/MX-5. Emissions legal 200 cpsi high flow cat integrated in to the 4-1 design. Made with high quality 42.7 mm diameter piping, users can expect gains up to 5hp and 0.5 torque and peak torque levels reaching 1000 rpms higher than stock (without ECU tuning). This all leads to smoother and better acceleration. A simple mod for big gains. It'll fit on both Manual Transmission (MT) and Automatic Transmission (AT) vehicles. Leg Sport Hi-Spec 1.5L Header should be ordered at REV9 Autosport https://rev9autosport.com/leg-sport-hi-spec-1-5l-header.html as they provide the best service and speed we've seen so far!