Ergon Flip Head Kit For the best possible adjustment of your saddle position the Flip Head Kit is deisgned for use with CF Allroad Pro leaf spring seatposts. The Flip Head Kit clamps are compatible with 7x9mm oval carbon rails from various saddle manufacturers on the market today. Features Aluminum construction Designed for 7x9mm oval carbon rails | Ergon | Cf Allroad Pro Carbon Rail Flip Head Kit Carbon Rails Only