My girlfriend had several used lip balms that either had missing caps or loose cracked caps so I decided to revive them with some 3D printed replacement caps!
The model is quite basic, just a hollowed cylinder with some fillets. This lip balm format has a ridge on the balm cartridge itself, which is how it keeps the cap secure and gives it that clicky feel when taking off / putting it on.
I printed using PLA because it is food safe and prints the cleanest, but you can use any material. Make sure to clear out any blobs from the inside of the cap before use. The first time you put the cap on it will take a decent amount of force, but after a day of use it will loosen up and move more freely.
The author hasn't provided the model origin yet.