The air pump adapter simplifies pumping up the lamp by replacing it with the hand pump. To do this, unscrew the pump cover together with the piston and screw on the air pump adapter. An air pump or compressor can then be connected to the adapter to quickly and conveniently pressurize the tank. If the lamp is pumped up with the help of the adapter, this also benefits the service life of the bulb. Shocks caused by pumping with the hand pump are thus avoided. The air pump adapter fits all Petromax models: HK150/250/350/500.