Just keep DEET away from any plastics and stretchy materials containing spandex/lyca. That includes stretchy softshell pieces. I prefer applying via lotion. Once I’m done with the application I pour some water on my palms and rinse them dry.
It’s my experience that a 20% delayed-release concentration is flawless in just about every situation in the Northeast. Please note that I sweat buckets no matter how much I skimp on layers. In that regard, the delayed-release stuff is gold! I base this not only while hiking (when black flies and the like have trouble keeping up) but while climbing (masochists would revel in belaying sans DEET in Spring up here).
IIRC, you don’t gain a lot more by going for any concentrations greater than 33%. That jives with my experiences.
I know some outdoors folks have pretty strong criticisms of DEET, but it’s right near the top of my essential list of gear. Given how much I sweat and how many critters I seem to attract, I don’t think I would be able to enjoy the outdoors without DEET.
Man, I didn’t even realize the stuff could be applied with a roll on! Thanks for the heads-up.
Happy trails!