The Tri-Backup Elite is designed to position two cage mounts, Two 16g Co2 cartridges, and 1 Micro AirBooster inflator behind the saddle Designed to be used in conjuction with standard saddle rails, for vertical triathlon seat rails use the Elite 90. Compatible with Ninja TC Road, Ninja Pouch+ Road, and Ninja CO2+ Tri-Cage accessories Includes Micro AirBooster inflator and 2 16 gram cartridges Tri-Backup Elite BlackUPC/EAN/GTIN: 883466011816