I have 2 Black and Decker Air Station electric pumps, one at least 30 years old and a 'newer' model purchased within the last 10-12 years (for road bike tires). Previously replaced an air cartridge on an old (car tire) pump by buying a cheap pump and replacing it with an air cartridge. However, air cartridges on both pumps became a problem, ie. leaked and jumped out of the tire valve stem under load. Found this dual ammo set at Revain and said it was a hell of a cheaper and easier fix than buying a bunch more cheap pumps. This is a simple cartridge removal and replacement procedure. Since 2 clips come with chucks, this is even better. I emphasize simplicity because I had a stroke in March 2022 and was still only able to use my dominant hand. Tip: Use a 6mm socket on the jam nut (easier than a one hand screwdriver). Also, I'm 77 years old. These new cartridges keep my air pumps looking like new. I just inflated my road bike tire to 110psi and it was hands-free development. I hope to get back on the bike in the near future.