Abstract: A tapered tubular casing of sheet metal has an open upper end and a closed bottom end. Sheet metal connectors having upwardly and downwardly directed tangs are spot welded to diametrically opposite portions of the casing adjacent the upper end thereof. The upper ends of two flexible chains are attached to holes in the lower tangs. One chain is somewhat shorter than the other, the shorter chain having an open hook attached to its free end and the longer chain having a snap hook attached to its free end. When the device is in use to keep an ice fishing hole from refreezing, the open hook is releasably fastened to an eye screw anchored in the floor of a fish house and the snap hook is similarly releasably fastened to a second eye screw.