Abstract: A propellant strip assembly for use in propellant actuated fastener driving tools. The assembly includes a carrying strip which contains a plurality of pockets which each hold a propellant charge and a sensitizer to activate the charge. The carrying strip is adhesively joined to a cover strip to isolate the individual charges, and each pocket is also sealed around its periphery to further improve the isolation. The cover strip may contain a ribbed section to physically separate the charge and sensitizer within each pocket to aid in prevention of accidental ignition.