Topeak Airbooster_G2 Gauge Black. The Topeak Airbooster G2 CO2 inflator with tire gauge provides tire inflation and tire pressure measurement. The angled head fits Presta and Schrader valves and a special feature allows the user to adjust the flow while filling the tirePresta / Schrader with integrated dust cap Push to inflateDual end design allows cartridge storage for 1 threaded 16g / 25g CO2 cartridge160 PSI Gauge