Abstract: A device for filling pneumatic tires. The device includes a container for gas under pressure and upon which a dispensing head is mounted. The head has a passage leading from the interior of the container and there is a tire valve in the passage movable to opened and closed positions. An orifice in the passage inwardly of the valve has a flow capacity less than the valve to determine the maximum flow rate of gas from the container. The dispensing head has a sealed and threaded connection to the container and there is a relief port connecting the passage at a point between the valve and orifice with the threaded connection inwardly of the sealed connection and effective to bleed gas from the container to atmosphere when the dispensing head is unthreaded from the container far enough to break the sealed connection but before the threads are completely disengaged.