This is a high intensity cold light source using a Quartz Halogen Lamp. It is used in conjunction with all Microscopes, G & H Series Borescopes and Micro-Probes. It has to be purchased as a separate item for all Fiber Optic Ring Illuminators, FOI-1 Bifurcated Bundles, FOI-2,3,4,5 and 6 Light Guides. It has a variable intensity Control. The unit has an internal Fan System to assist in cooling and prolonging bulb life. The Fiber Optic Light Guides or accessories are not included. The Illuminator comes equipped with a basic .625" opening for all Titan Light Guides and Ring Illuminators., Input Frequency: 60 HZ Power: 120 V 3 Amp Lamp: 21 Volt 150 Watt-Halogen 3400 Deg. Kelvin Length: 7.5" Height: 6.5" Width: 7.0" Weight: 7.5 lbs. Delivery on 220 Volt FOILB is 14 days.