Suggested Retail: $189. Riva Racing - FX Free Flow Exhaust Kit The Riva Racing FX Free Flow Exhaust Kit replaces the restrictive sound suppression system between the waterbox and hull exit on your watercraft. It improves engine performance by reducing back pressure and harmful detonation. This kit is designed for easy installation and offers noticeable results. The product is race legal, making it a reliable choice for performance enthusiasts. Brand: Riva Racing. [Reference: eqaks9Mjr5oTFIn8BEcV9F]. LOT STICKER: OH001-00000600-28. Type: Regular. 7 CALENDAR DAY FULL REFUND GUARANTEE (FROM PRIMARY PICKUP DATE) ON THIS ITEM IF ANY ISSUE IS FOUND THAT WAS NOT DESCRIBED/PICTURED. 7 CALENDAR DAY STORAGE (FROM PRIMARY PICKUP DATE) IS ALSO AVAILABLE. THE PRIMARY PICKUP DATE IS THE DAY AFTER THE AUCTION ENDS. SEE NOTES TO BIDDER, IN AUCTION DETAILS, AT THE TOP OF PAGE 1 FOR MORE INFO.