TFSeven Mini Q5 450 Lumens Waterproof Pet UV Urine & Stain Detector, Blacklight/Flashlight, Find stains on Carpet, Rugs, Two 18650 Batteries & Charger Included (Purple Light UV) UV-A flashlight shows hidden pet stains and other unfavorable spots on carpet or clothes Aluminum alloy casing with o-rings for water resistant design.as compared to 501B it has a belt clip Use it to authenticate notes, currency, documents, and passports Power by: 1 x 18650 Rechargeable Li-Ion Battery (Package included) Small size can be taken anywhere or easily stored