PasLode 650039 Short Yellow Fuel Cell 4-Pack Patented 2-step cap to prevent fuel waste Ready to use when cap is clicked from front-to-back Use before expiration date for maximum performance (marked on bottom of container) For use with PasLode 900600, 902000, 901000 or other fuel powered cordless nailers (sold separately) Not for use with PasLode CF-325 Fuel Powered Cordless Nailer