These caps are made from Delrin White or Black and allow for easy filling of your squonker bottle so you dont have to take it out. They fit 30 ml gorilla bottles currently among some others I have come across.. I made these from Delrin to save weight and save your threads of your 510 fitting.. Nobody wants a 3 lb metal cap in the pocket do ya ?!!?? No threaded cap here to loose and equally have more work on your hands....Comes with a friction fit pull cap for easy access... yet stays on and seals up tight!!
**obviously not child proof so please be responsible!