CAT 25 Generator Module is composed of a CAT 25 structure with a stairwell and remotely controlled hydraulic hatch.  Three slow speed water cooled diesel generators are located near the center of the structure with 4,750 gallons of fuel under the floor.  Cooling and combustion air is filtered by 4 MCAS 600 NBC air filtration units supplying breathing quality air.  This module includes, a battery bank, lighting, decontamination stations, storage under the floor, AC washer and Dryers, trash compactors, and spare parts. This unit can operate as a "stand alone" unit but is usually connected by tunnel to another structure. Exhaust and cooling air are mixed to avoid thermal signatures by ground and airborne target acquisition equipment.