Light Source Premium V-bin LED selected for brightness and color tint (pure white) rated at 240+ Lumen by manufacturer Operating Life LED 100,000h (11 years) Optics Hyper Prismatic Reflector (HPR) technology optics providing a narrow half angle beam divergence of only 6 degrees with excellent dispersion characteristics over the entire beam angle. Brightness Regulation Proprietary regulation circuitry maintains constant light level as battery voltage drops. Dimensions/Weight 3.5'' x 1.125'' Weight (with battery): ~100gr (3.38oz) Battery 3V CR123 Primary Lithium. To replace battery simply unscrew the knob in the back. User Interface Push button switch with momentary functionality and a rotary knob to adjust brightness. Low Battery Indication When set to full brightness flashlight maintains constant brightness level. When full brightness can’t be maintained anymore (battery low) brightness level drops. After a while the light will begin to strobe – indicating that battery needs to be replaced. After a while the strobe stops and the light can still be used at a very low brightness level for about an hour – until the 123 battery is fully depleted. Multi Brightness Levels: Unlimited regulated brightness levels are available by turning the knob in the back allowing either maximum brightness or maximum runtime or any setting in between. Water Sealing: The light is designed and built to be fully submersible – however individual units have not been tested by submersion. As a result the official rating is “water resistant”. Materials: The exoskeleton of this light are made of grade 2 and grade 5 Titanium. The thread of the back knob is gold plated copper to prevent galling (thread locking) often found with titanium threads. The battery tube is made of light weight carbon fiber composites with a ground & varnished 4x4 twill weave cosmetic layer. Gold plated contacts for minimum electrical resistance and corrosion protection. Machining High precision components with <0.0005’’ (0.01mm) tolerance. Machining surface finish of less than 4 Ra Assembly: Each GatLight is carefully hand assembled by skilled aerospace technicians. Number of Parts: Each GatLight consists of over 80 parts. 42 parts are custom machined metal parts. The 24 screws are custom made on high end Swiss screw machines, since stock screws did not meet the quality demands for this light. Serial Numbers: Each GatLight contains a unique laser marked serial number showcasing the limited production of this product. Accessories Each GatLight comes with an attractive solid wood display box with a bronzed Lumencraft logo. Comes with a wooden display box. Has a couple light scratches, otherwise excellent condition.