Redshift Shock Stop Pro Race Suspension Seatpost Go fast, comfortably. For decades, companies have tried to build in vertical compliance and a softer ride with new seatpost designs, but Redshift has taken it to the next level with the Shock Stop Pro Race Suspension Seatpost. This advanced seatpost has a minimalist, lightweight design that fits perfectly with modern gravel and road bikes, while effortlessly absorbing bumps and road vibration to reduce fatigue and increase comfort. This added comfort helps riders go further, faster, with 20mm of active travel. The race-tuned Shock Stop Pro Race reduces weight, up to 130 grams, from the original Shock Stop Seatpost, and uses a progressive spring rate for a firm pedaling foundation. Go faster, go comfortably with the Redshift Shock Stop Pro Race Suspension Seatpost. Features Built-in high-performance suspension with 20mm of active suspension travel Pro-level Shock Stop features a race-tuned design of coil springs and elastomers, for a firm foundation without compromising suspension25% weight reduction (up to 130 grams) compared to the original Shock Stop Seatpost Shimano Di2 battery compatible to accommodate an internal seatpost battery Optimized linkage geometry for an ultra-responsive feel Two elastomers included Green (Soft) elastomer pre-installed, Red (Medium) included in box Specifications Seatpost Diameter27. 2mm Included in Box Shock Stop PRO Race Suspension Seatpost (pre-installed outer coil spring, inner coil spring, Green elastomer with end caps)Seatpost Offset7mm Material6061 T6 Alloy | Redshift | Shockstop Pro Race Suspension Seatpost 27. 2Mm X 350Mm, 20Mm Travel | Aluminum