Heilyser Oxalic Acid Vaporizer
Oxalic acid is an excellent treatment for Varroa mites, especially when the hive has little or no brood. In Maine, we use it in October, December/January, or in early spring.
Runs from the power of a 12 volt (car) battery. Uses 1 gram of oxalic acid crystals per deep hive body. Pure oxalic acid is available here.