The Guinevere Inflatable Sanders are pumped up through an air inlet in the drive shaft located in the bottom of each sander. The molded rubber bulb constantly flexes and changes shape conforming to the shape it is pressed against. It should be inflated with the minimum amount needed to hold the rubber bulb on the mandrel.
This small sanding head measures 3/4" in diameter. To inflate use the Micro Hand Pump offered below. Do not use compressed air as it can damage the unit.