fox shox 2018 fit4 remote topcap interface Genuine replacement parts for Fox suspension components. Non-remote FIT4 cartridges can be upgraded to remote via the installation of a complete FIT4 Remote U-Cup Topcap Assembly. This ensures the optimized topcap configuration with friction-reducing features for the most reliable remote installation possible. FOX recommends PTU remote systems over PTL systems as they are optimized for reliability and reduced lever force. The FIT4 topcap "butterfly" valve must be matched to the appropriate lever/topcap interface parts. Installation of FIT4 Remote Topcap Interface Parts on a FIT4 3 Pos or 3 Pos Adj cartridge does not convert the cartridge to the optimized remote configuration even when used with a 3 position remote lever as the standard FIT4 3 Pos or 3 Pos Adj topcap does not contain the U-Cup that optimized remote topcap friction. Features Manufacturer part number:820-05-455-Kit Genuine Fox components Remote not included | Fox Racing Shox | Fit4 Remote Top Cap Interface 2018, 820-05-455-Kit In Black