Whether we are serious racers or just weekend warriors, we can all benefit from the premium performance of the RockShox SID Ultimate Race Day 3-Position 29in Boost Fork. Featuring excellent performance for cross-country racers, the SID Ultimate 3-position fork is super lightweight and ultra tunable and has a 3-positon compression switch so we can adjust our compression on the fly for changing trail scenarios. The DebonAir+ air spring offers enhanced small bump sensitivity and mid-stroke support for more performance in the beginning and middle parts of travel. Additional features of the RockShox SID Ultimate Race Day 3-Position 29in Boost Fork include a machined hollow aluminum crown and magnesium lower legs for weight savings and upgraded bushing for a smooth ride.