I got my Dawn PD in Kissimmee Fla. I think it was about $3. The full store had none, as did most other ones I looked at in Canada and the Detroit area. The store I found was just the grocery Walmart. I like to use it because I don't have to take the motor apart and remove the rubber and plastic. Sometimes I leave it in the plane, not that I am lazy? I haven't tried it on a gas motor, but the glow ones work nice. I had some pretty crusty looking examples.