Formic ProFormic Pro the next generation in formic acid treatments and is used to treat hives with varroosis, caused by varroa destructor in honey bees. Unlike Mite Away Quick Strips, Formic Pro has a longer shelf life of 24 months and no temperature requirements. Daytime temperatures still must be between 50 F 84 F (10 C 29 C). Strips are laid across the tops of the brood frames. Safe to use during the honey flow! A spacer rim is no longer needed for these