These are some butane lighter refill adapters/nozzles. The adapters/nozzles that came with the can of butane never fit my lighters quite right, so I made my own. I had the best results when they were printed with a 0.25mm nozzle.

Note that there are different files for PLA and TPU. They have slightly different dimensions due to the TPU being flexible and squishing when pressure is applied to refill. I have included the Solidworks and STEP files if you want to try to change it up to suit your situation.