Ultrathon Insect Repellent – Do you need an bug spray that’ll last? Ultrathon Insect Repellent was originally developed for the U.S. Military. What do you have to say about that? With 3M Controlled Release Technology you’ll find yourself receiving protection from all kinds of bugs for up to 8 hours. Protect yourself from those pesky gnats, mosquitoes, ticks, chigger and biting flies.