Knapsack Tank 3 : Brit A small, portable tank of up to 4-gal capacity carried on an individual's back and used to feed a foam compound to a small foam-making branch
Ralph W. Burklin & Robert G. Purington, Fire Terms: A Guide to Their Meaning and Use, National Protection Association, Boston, MA 1980 USA. (Guide: Meaning and Use, Nat Prot Association Fr Srvc - Amer) {457}