Rug Doctor Spot Detector, Finds Tough Stains Using Ultra-Violet Light, Use on Carpet Floors, Hardwood, Tile, Furniture, and More The Rug Doctor Spot Detector uses a bright UV Black light to illuminate stains such as urine, feces, vomit, saliva, and blood The compact size of the Spot Detector allows it to be portable and easily accessible. Its an easy to use lightweight, hand-held stain finder. The ability for you to use AA-batteries (not included) in the Spot Detector allows for it to be cordless and easy to carry anywhere. Use to find hidden spot and stains on carpet, rugs, upholstery, mattresses, walls, pet beds and any floors. The stain will glow when using your Spot Detectoronce the stain is found, use Rug Doctor Platinum Urine Eliminator Spray or Rug Doctor Oxy Pure Spray to remove.