Fold a bandana a few times loop a rubber band about 1/4 inch from each end and fold the ends over the rubber bands. Hold the folded ends so that the rubber band loops are extended. Loop the bands over your ears for a nice quick mask. Bandana and two bands .. really nice!
Wanted to use these rubber bands for diy face masks. They are definitely big enough. You will need to tie a knot on one side of the rubber band to adjust how big you need for the ear loopholes. A 3.5 diameter rubber band would probably work better for the diy masks but these are good if you want to be able to adjust.
I bought these rubber bands as part of "moo masks" to protect against the corona virus. The bands go over the ears to hold the mask in place. The rubber bands are adjustable (just tie a knot in it at the right point to fit your head). They work fine! I've made over 30 masks and donated them to a senior center and am on my second bag of rubber bands. They are consistent and serve my purpose well.