I've got one made by Red Cap, apparently they give Osha the fits when talking about them. They had a buy back of the things or something like that due to some law suits. They work good, but you have to start it in order, and shut it off in order. DO NOT TRY TO ADD FUEL WHILE ITS STILL WARM!!!! Start up is as previously mentioned. Shut down should be close the carb till it cools down, then close the damper, and cover the cap. I did it out of order once and it sounded like a shot gun. If you try to cap it while still hot, it will smolder for hours. I run 50/50 waste oil and diesel. It runs smoother and smokes less the more diesel you use. Wait till its cool to the touch before adding any more fuel