Stand up paddlers and other water sports enthusiasts looking for an alternative to traditional life jackets will love the NRS Zephyr Self-Inflating PFD. It's lightweight, easy to wear and inflates instantly to float you high. This lightweight self-inflating PFD provides 15.5 lbs. of flotation and meets U.S. Coast Guard requirements. (See Note below.) The compact, adjustable ripstop nylon waist pack stays out of your way for SUP or surfing. A simple tug on the cord instantly inflates the PFD with pressurized C02 gas. A 16 gram CO2 cartridge is included with the Zephyr. NRS CO2 Re-Arming Kit, Item # 40035.01, is sold separately. It's a good idea to have extra re-arming kits on hand. Unlike many other self-inflating life jackets, the flotation chamber stays around your waist. Simply rotate the belt until the chamber faces forward, pull the inflation cord and secure the attachment strap over your head. A manual mouth valve backs up the CO2-powered inflator. The bag's clear window lets you check the inflation system for readiness. This PFD carries the US Coast Guard Certification, through testing by Underwriters Laboratories (UL). If you are flying with your Zephyr Inflatable PFD, the Transportation Safety Administration (TSA) says on their website, "You may bring a life vest with up to two CO2 cartridges inside, plus two spare cartridges in your carry-on or checked bag." Be aware that individual TSA agents may not have read that particular regulation. Note: This PFD is certified by the US Coast Guard as a Type V PFD. However, it meets Coast Guard requirements for Type III PFDs when it is worn. In other words, you have to have the pouch secured around your waist for it to qualify as a required flotation device.