You’ll be much happier if you buy the adapter hose to connect the little heater to the larger 20 propane grill tanks. They’re readily refilled, run the heater for days, and the little green cans are stupid expensive. That’s how we use the little heater in the bunkhouse at camp.
To use the larger tank on a Buddy Heater you need to buy the inline filter or the special 10 foot non-leching hose because the normal propane hoses leach petroleum droplets which clog up and ruin the Buddy Heaters.
On stoves and such the leaching doesn’t matter in the open flame but with the Buddy Heater it clogs the safe for indoors catalytic burner instead of burns off.
This is the portable heater that I’ve often used for emergency use... not that expensive and all one needs is a propane tank or two sitting around (or take one off the barbecue). I’ve bought a few of this type..... works well but I did run into a problem with my last one though... bought a new heater and a new propane tank for the cottage and I could not get the propane to flow.... I’m assuming that there is a pin that needs to be depressed when the heater is screwed on to the tank and somehow it just wasn’t engaging properly even though the heater seemed to thread on just fine. I never had that problem with any of the other ones I’ve purchased but I’d recommend testing it right in the parking lot so it can be returned if necessary...