The lights are tuned to work in the 385-390nm range of the UV spectrum and waste very little energy in the spectrum of light that doesn't cause the molecules in urine to fluoresce. Translation: more battery power is devoted to detecting urine stains, not lighting the room. The UV light is water resistant, shockproof and the rugged aluminum body will protect your light from mishaps in the van. LED lifetime is an impressive 100,000 hours and will run for hours on three AA batteries. Batteries are not included.