Dave is correct, it is a Butane fired system on that engine.
Besides getting a can of Butane fuel to charge that tank, you may also need a special nozzle, depending on the kind of Butane source canister you are wanting to refill from. The low-profile camping fuel type of Butane canister will require a special nozzle, which is not hard to find nor very expensive. If you obtain the other type of Butane canister, it will possibly work just the way it is intended to be used to refill cigarette, B-B-Q & stove lighters, Bernzomatic torches and other such Butane fueled items and may well work as purchased, depending on reach. If it won't reach your tanks filler valve, then again, there is an after-market extension adapter that can be purchased to make the reach.