The Kit has been designed following the US Department of Agriculture requirements. The water tank, with a total capacity of 3,500 lt., is divided into two independent compartments. These compartments are discharged through 6 doors at each side of the fuselage. The doors are gravity opened and hydraulically closed. The hydraulic system of the water tank is connected to the hydraulic system of the aircraft, employing security cut-off valves to isolate it in case of leaking or malfunction.

An electrical system exists to control the water discharge, the doors closure and the isolation of the water tank hydraulic system if any failure appears. Additionally, there is a hand operated hydraulic cut-off system in the cockpit just besides the pilot's seat.

There is an emergency system to discharge the water to be used in case of normal function failure. The emergency system is operated with a lever in the cockpit, just besides the co-pilot's seat. The kit is installed inside the aircraft and fixed to the cargo bay floor with screws. The installation is simple and does not interfere with the rest of the aircraft systems. Likewise, the kit can be removed very easily, so the aircraft can be used for fire fighting or cargo tasks. Once the kit is removed, the aircraft recovers all the cargo capabilities, without any reduction in weight or in volume. The aircraft needs to be modified to install the kit. The modification consists of the opening of doors in the fuselage to install the discharge pipes and the installation of the structural reinforces to recover the original aircraft characteristics. 

The aircraft modified for fire fighting has no restrictions in its basic performances due to the installation of the kit.