Retro fit XV (Extra Volume) can for upgrading standard DBair's.The XV can offers a higher air volume and is perfectly suited to bikes with a significantly progressive leverage ratio, such as Intense and Santa Cruz. These bikes require a more linear air spring. The less progressive air spring allows the rider to ride with more High Speed Compression while still achieving full travel.Here's a video from Malcom at Cane Creek showing how to remove and refit the air can;