Skipping ahead here, but just wanted to throw in a little science, so you aren't duped by misleading statements by marketing groups like those that sell those magnets making fantastic claims.
An infrared lamp is nothing more than a lamp designed to release most of its energy as heat rather than light. Its what keeps hamburgers warm at McDonalds and reptiles warm in their enclosures. Expect warmth, no more or less.
Applying cold or heat to joints has been used for centuries, so that is certainly valid, but just don't expect anything different than if the cat were to simply sun on a window-shelf for free or toast his furballs on a room heater or quad-core laptop. 
Lasers have to be second only to magnets on unsubstantiated marketing claims. If powerful enough, they can cut and cauterize due to very directed application of heat, and are thus excellent for use in medicine or various industrial cutting applications. However, we surely don't want to be cutting joints and weak lasers are not going to regrow hair like you see with cheapo products online or really do much of anything other than entertain your cat if you point it on the floor or wall and move it around, as otherwise it is nothing but directional light with wavelength in phase to produce a single color.