One of those heaters filled with oil, with fins and plugged into the electric. I've used them before but need another one now....unfortunately, I have been to two Warehouses, one Mitre 10 and one Briscoes and was unable to find any for sale. Dehumidifiers, desk fans and patio heaters- take your pick. This was mid February though so perhaps retailers thought it wasn't yet cold enough for people to need them. Well, now it is!