Technically all incandescent and halogen light bulbs could be called heat lamps because, at all wattages, they are more effective at generating heat than light. In practice, 125 watt to 375 watt incandescent reflector bulbs are used for heat lamps in homes, warming lights for food service and in brooder applications. For commercial and industrial applications, tubular fused quartz infrared heat lamps produce intense levels of infrared radiation. Wattages for these lamps range from 300W up to 2500W and many operate at higher voltage.

Xushi Bulb heat lamps mainly apply reptile, for example Reptile Moonlight Black Light Bulb and Reptile Basking Spot Lamps.
Reptile Moonlight Black Light Bulb