This is the Boost version for bikes with 12 x 148mm rear spacing

the fit and vents are adjustable on the fly

Fusion Comfort Technology ensures that you'll have ample support when on the wall

SIL-TEC on Plate/Roller

Wider and longer pedal–shoe contact area transmits power efficiently and improves bike control

Ultra-Sil Pack Cover Size:large This is the Boost versionSea to Summit Ultra Sil Pack Cover The Ultra Sil Pack Cover ends the debate about whether you should carry one or not. It's a tiny and compelling solution and the medium size weighs less than four ounces. Plus it packs into its own small stuff sack why wouldn't you carry one? Features: Made of 30D Ultra Sil fabric constructed from CORDURA yarns for durable, waterproof performance. This pack cover does not use seam construction to ensure that it is