The M.I.T. 100 Inflatable Re-Arm Kit contains everything necessary to re-arm your, Mustang Survival M.I.T. 100 manual, and automatic inflatable PFDs, after deployment. One 24 gram CO2 cylinder and bayonet assembly One bobbin One re-arming instruction manual The automatic inflator bobbin on all automatic PFDs should be replaced on a regular basis For model numbers: MD2014, MD2015, MD2016, MD2017 Use only Mustang Survival re-arm kits Use of other re-arm kits may result in improper operation, or failure to operate, and will void the product&';s warranty