AC-40 is a potassium acetate that is meant for use with the Badger Extra Water WP-61 extinguisher (item # 09624). It allows the extinguisher to be used in cooler temperatures down to -40°F (-40°C). It is meant for use against class A fires. This product is 10 lbs and is meant to be dissolved into 15 pints of water.
Downloads available: Safety Data Sheet (SDS) for AD-40.