Usage: 1. Weigh the unused butane canister and write on the base with a marker. 2. Place the empty canister for about half an hour or overnight. 3. Take the canister out of the freezer and place the adapter on the canister. Take your new full butane canister and insert it into the adaptor. 5. Press firmly on the bottom for 10-15 seconds and each time check the weight of the canister until it equals the original weight indicated on the base. It weighs only 5 g, allowing you to easily carry it when hiking and camping. With this adapter, you can fill your gas can as if you were using a cigarette lighter. You save a lot of money when you refill the product. Warning: Once you have filled the canister, it is always a good idea to check the seal of the canister to prevent leaks. Only fill your canister in a well-ventilated area, outdoors Please note: without gas tank. Function: 1. Material: copper. 2. Weight: 0.0088 kg. Contents: 3 gas refill adapters. Lightweight: it weighs only 5 g, so you you can easily carry it while hiking and camping. Material: Copper Warning: Only fill your water bottle in a well-ventilated area, outdoors. Scope of delivery: 3 gas refill adapters