I photographed these M149 400-gallon Water Trailer examples at Oshkosh, Thermopolis and the NMoUSAF. The M149 and M106 Water Trailers both have a 400-gallon capacity, but the fiberglass tank on the M149 cuts the weight almost in half (2,800 lbs for the M149 compared to 5,512 lbs for the M106)