Too regularly, convenience comes at a cost. Often, that cost is waste, both material waste and energy waste. One particular convenience I always find hard to know what to do with easily is gas cartridges, the Butane/Propane mix canisters many of us use with our stoves. There are ways to dispose of the canisters, but puncturing them easily, and safely is quite difficult. A hammer and screwdriver may well be one way, but how safe is hammer metal surfaces together near the possible remnants of what was in the canister? Well I've found my solution to the problem which also allows for the canister to be more easily recycled.
Jetboil, producers of the SOL, ZIP, Flash, etc have produced the CrunchIt, a solution to safely make gas canisters disposable. The CrunchIt is made from stainless steel and has a bottle opener and jet orifice wrench for the Jetboil stoves. It weighs only an ounce (28.35g) for the weight watchers and has a protector on the pointy bit so you don't damage your gear or your self accidentally.
Using the CrunchIt is fairly straight forward as long as you follow the instructions. Firstly you need to make sure that the canister is empty, there may be a tiny amount of gas left, but ensuring it is as empty as possible would be a good idea. Once empty, the CrunchIt is screwed on to the canister, an action that releases any tiny amounts of excess gas. It is screwed on tightly, and then after removing the protector on the point, pushed down onto the canister using the area where the recycling icon is. On my canister I punctured it three times so as to ensure all gas would be released.
The CrunchIt is fairly cheap, around £6 and does the job safely. I would make sure it is safe to dispose of the canisters where you live after puncturing, the idea being that the canisters can be safely recycled. And the great thing, it works on non-Jetboil canisters as can be seen in my photograph.