Formic Pro Strips, 10 Dose -20 strips. Formic Pro™ is the next generation in formic acid treatments for mites. The strip is thinner than the height of a bee so it fits in the bee-space between hive parts making it much easier to apply. Formic acid is one of Nature’s defense chemicals, found in plants (nettles) and ant venom. Formic acid is a naturally occurring component of honey. 2 strips per treatment, so 20 strips will treat 10 hives.