The 1F Automatic and 3F Manual Inflatable PFD Re-Arm Kit E, contains everything necessary to re-arm your inflatable after deployment. The automatic inflator bobbin on all automatic PFDs should be replaced on a regular basis. Note: This re-arm kit replaces discontinued re-arm kits MA7202 and MA7203. 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. Re-arm kit contains: One 33gram CO2 cylinder, one bobbin (use only with automatic inflatables) and one re-arming instruction manual. Kit is compatible with inflatable PFD model see SKU&';s: MST2981 and MST2983.