Propane, to be sure, but I have never seen another stove quite like it. Basically a 2 lb. propane bulk tank with stove permanently attached. It's a little bigger and heavier than your average backpack stove, but may see a little use in the canoe or back porch. I found a friendly propane man willing to fill the tank, it's the old style reverse internal thread filler, but the tare wt. is clearly marked on the tank and it's in very good shape. Here's a 71 with it for scale. I've been using it in the garage as a cooker/heater of gas stove parts!