{
ItemScubaTank tank = (ItemScubaTank)mc.thePlayer.getEquipmentInSlot(3).getItem();
final int max = 300;
tank.useGas(mc.thePlayer.getEquipmentInSlot(3));
GasStack received = tank.removeGas(mc.thePlayer.getEquipmentInSlot(3), max-mc.thePlayer.getAir());
if(received != null)
{
mc.thePlayer.setAir(mc.thePlayer.getAir()+received.amount);