The Oil Reservoir is a 2.5 liter tank with vented fill cap that holds enough oil for up to 30 gallons of main tank flow providing for up to 10 hours flight time without refilling. Below a certain oil level, a dash light (not provided) will signal the pilot, thus avoiding the possibility of engine failure due to a lack of lubrication from an empty reservoir. Can be easily mounted to the firewall as long as unit is located above the level of the pump which must be gravity fed. Includes hose, filter, tank fitting, two mounts and sender. Size: 9" W x 7" H x 5" D.