The Hinkley Lighting 1539BS Underwater Pond Light Brass is an underwater light fixture which operates on electric current of 12 volts to power a 50 watts bi-pin bulb contained in a 4.75Â wide lampshade held in a 6Â high brass finish enclosure. Since the 1539BS Underwater Pond Light is placed inside ponds or swimming pools, the entire assembly is highly resistant to water leakage and seepage. This resistance is measured in terms of IP rating of the 1539BS Underwater Pond Light. The IP rating of any light fixture consists of 2 digits, with the first digit signifying resistance to solid particles such as dust and the second digit signifying resistance to water. While the range for the first digit varies from 0 to 6, that for the second digit, between 0 and 8, with 0 implying no resistance to water ingress and 8 signifying extreme resistance even when immersed under a meter of water. For underwater operation, the second digit of the IP rating should be 7 or 8.