Gonna use substitution later today, pre-employment. I tried with an at home test the other day with dilution, not much luck there. but, for anyone needed a subbing strategy, I'm goin with swimming trunks under the pants. The string will keep your container from droppin out your pant-leg, and the netting in the shorts will keep it nice and close for good heat, just to be sure I'm bringing a thermometer and using handwarmers banded to it with rubber bands. I'd rather have to cool down than figure out how to warm it up while I'm standing in a little bathroom with empty pockets.