Product Description DT-2 Drain-O-Tank Air Charger. Drain water and pressurize tank with one valve Drain-O-Tank Air Charger. DT-2 DRAIN O TANK PLUG 1/2". Replacement Part. From the Manufacturer DT-2 Drain-O-Tank Air Charger. Drain water and pressurize tank with one valve Drain-O-Tank Air Charger. DT-2 DRAIN O TANK PLUG 1/2". Replacement Part.