This lamp is Mega-Ray's top-of-the-range 160 watt SB Par-38 Narrow Flood Lamp which has been shown in tests to produce similar amounts of UVB to natural sunlight! - along with adequate heat to create a basking spot at the recommended distances in many circumstances.Mega-Ray?« SB 160-watt narrow-flood is a 160-watt SB Par-38 True Frosted Flood Lamp. A true flood lamp it will disperse usable UVB in a 30 circumference at a 20 distance. MINIMUM distance setting of 18 will produce approximately 150-200 microwatts per square centimeter (uW/cm2) of UVB and 900-1200uW/cm2 of UVA. MAXIMUM distance setting of 24 will produce 50-75 microwatts per square centimeter (uW/cm2) of UVB. (Distance is measured from lamp face to basking spot or reptile for optimum UVB and heat.) Most people with UVB meters are getting 18+ months use out of our SB bulbs.