https://www.amazon.com/Dr-Bronners-P.../dp/B00120VWJ0

Dilute heavily into one of those cheap TSA-approved <3oz bottles for transport, or hide a big jug at work. Experiment to find the right mix so you can soap up and rinse off quickly. Best stuff ever for swamp crotch as long as you dilute it enough. Too strong and you'll feel like you're humping a block of dry ice with Vicks for lube for the next hour. Also works for hair, face, shaving, armpits, and degreasing car engines, though preferred dilution levels may vary.