A device for killing insects, such as bedbugs, with heat includes four side panels and two end panels. Each of the side panels is fixed to two adjacent side panels along complementary mitered edges provided with interlocking male protrusions and female indentations. The side panels are fixed to the end panels by portions of the side panels that mate with complementary channels provided by the end panels and locking mechanisms. The device further includes a mechanism located either inside or outside the device for providing heated air to the interior of the device and a mechanism for circulating the heated air inside the device for killing any insects that may be infesting items such as clothing and bedding placed inside the device. The interior of the device may be provided with mechanisms such as racks and hanger rods for supporting items placed inside the device. The interior of the device may be provided with mechanisms for directing the flow of hot air inside the device.
