It is possible to find tight fitting caps that are not screwed on to garafons without threads that are very nearly drip free. If you find one, keep it and cherish it. We never found threads needed, besides, in many situations you are exchanging the garafons themselves (so you can keep that cap) and would lose your threaded one doing this. As well, the threaded ones that I have seen (and I have one) have a narrower neck. If you are using the Mexican bombos to pump your water, you will need one that fits the narrower neck. We have both, big deal, they cost about 3 dollars, so whichever garafon comes along, we are happy. It serves our drinking and food prepartion requirements, cheap insurance for staying healthy in Mexico. And anywhere else! The main water tank is for showers unless we can place our shower tent out in the sun, with a garafon warming up.