Flukers Clamp Lamp is ideal fixture for basking reptiles, with a ceramic socket thats rated for incandescent bulbs and a convenient dimmer switch. The spring-loaded swivel head may be positioned to radiate in any direction, and the secure clamp instantly attaches to the rim of any terrarium. Ceramic socket for incandescent bulbsAttaches to the rim of any terrariumConvenient dimmer switch75 Watt Clamp Lamp is 5. 5" Wide150 Watt Clamp Lamp is 8. 5" Wide120 Volt clamp lamp with dimmer6' long power cordThis UL/CUL-approved lamp features a metal reflector for enhanced output, with a 6 foot power cord for your convenience. Directions: Set lamp at one end of terrarium (lets pet retreat to cooler side if desired). Provide structure allowing the pet to climb up toward the lamp. DO NOT put food or water under the lamp The dimming option does NOT work for compact fluorescent or mercury vapor bulbs. To use these bulbs the dimmer switch must be turned completely on. Important: Be sure to read all information regarding safe lamp placement and operation before use.