Product review (3 stars): Work but poorly engineered
I've had to buy a number of these to replace gas valves on my Kitchen Aid stove when they get stuck.  I believe this happens due to the open channel on the shaft that conducts cooking splash or cleaning fluids to flow down into the valve itself.  If the open channel was facing down, I don't think this would happen but it faces up by design.  I am now modifying these to seal the shaft end just below the knob so that liquids can no longer flow down into the valve.  This is working so far but its been very expensive thus far.