Abstract: A hinged two piece structure to remind an operator that a valve is on is disclosed. The valve shut-off flag is retained to a valve by a simple clamp and is therefore readily adaptable for use on many different types of valves, although the preferred embodiment has application on oxygen-acetylene torch sets. One piece of the structure acts as a support column for a hinge and a second piece of structure. The second structure piece partially covers the valve when the valve is in the closed or shut position. In order to turn on the valve, a user must lift the second structure piece to an upright position where it extends substantially beyond the valve. The second structure piece is of sufficient surface area and colored appropriately so as to catch the eye of a user.