Welcome to our store! 1. The De-cat Performance mid-pipe replaces both the primary and secondary catalytic converters Compatible with creating a free-flowing exhaust. 2. Direct mid-pipe replacement fits 125 250 390 RC390 2017+. Compatible with OEM silencers/mufflers and others that fit the original catalytic converter. 3. Superior 304 stainless steel with a thickness of 0.04 inches, shiny, heat and high-temperature resistant, durable in use. 4. Reduces heat and increases airflow, performance. The De-cat pipe weighs 770 g/1.7 kg, the primary and secondary catalytic converter weighs 4.01 kg, saving 3.24 kg/7.1 kg of weight in the catalytic section. Get everything from 5 to 6 hp, get the sound and performance by adding this mid-pipe. 5. No modifications needed. (remapping, power commander). The lambda sensor (O2 sensor) is located on the original front pipe which is retained and used with this upgrade. 1 x Exhaust Mid-pipe 1 x Screw Package If you have received your item and find any product problems, such as damage or incorrect quantity, please contact us immediately. We do our best Compatible with providing you with satisfactory customer service.