Usage: 1. Weigh the unused butane canister and mark the weight on the base with a marker. 2. Place the empty canister in the freezer for about half an hour or overnight. 3. Remove the canister from the freezer and attach the adapter to the canister. 4. Connect the full butane canister to the adapter. 5. Press firmly on the bottom for 1015 seconds, then check the weight of the canister each time until it reaches the original marked weight. This adapter is lightweight, weighing only 5 g, making it easy to carry during hiking and camping trips. Made of copper, it allows for efficient gas transfer. With this adapter, you can refill your butane canister safely and conveniently. Refilling helps reduce costs over time. Warning: Always check the canister seal after refilling to prevent leaks. Only refill in a well-ventilated outdoor area. Function: 1. Material: Copper 2. Weight: 0.0088 kg Package Contents: 3 gas refill adapters