Abstract: The invention relates to a pet toy that may be filled with food or scented material to attract and maintain the animal's interest while the pet tries to extract the material contained inside. The toy is preferably made with two nested housings with each housing containing one or more holes in the sidewall. Some of the holes in the housings may be adjustably aligned to create a opening in the side wall of the toy that permits materials inside the toy to fall out. The space between the housings is configured to trap crumbs or other particulate material that might create an undesirable mess if allowed to fall out of the toy.

Abstract: An infra-red radiation detector has a pyroelectric element (10), comprising for example TGS material, supported in spaced relationship over a heatsink body (16) for stabilizing the temperature of the element in operation with the space between opposing faces of the element (10) and body (16) containing a thermally-conductive, non-hardening and non-gaseous gel-like medium (22) such as silicon dielectric gel which thermally couples the element with the body. A small quantity of material such as solder or epoxy may be used to bond the element to the body and fix the spacing therebetween or, alternatively, the element may be supported over and bonded to the body simply by means of the medium (22) itself. Capillary action may conveniently be used to introduce the medium into the space between the element and the body.