Don&&';;t get stuck between dropper sizes. The unique OneUp travel adjust shims allow you to custom tune your OneUp Components Dropper post by lowering the travel and extended length of your post by either 10mm or 20mm. A 180mm travel post can be reduced in travel to either 170mm or 160mm with this shim kit. Drop tuning can be done on-bike, tool free and without removing the saddle or touching a shock pump. Lowering the post travel also increases bushing overlap and alignment pin length, which is great for heavier riders.