Laser Genetics ND3x40 Laser Designator Functions well in temperatures 40-deg. F or colder Green laser with Rotary Optical Collimator* 40x magnification Adjustable beam diameter & intensity Micro-beam is visible up to 3 miles Wider beam illuminates trails or "paints"targets up to 400 yds away Water-resistant Nitrogen-filled to prevent fogging (o-ring sealed) 532nm laser 40mW output Class 2M Uses 2 CR123V lithium batteries 1"tube 10"long 2"dia. lens 12.18 oz. Fully multi-coated lenses Made of high-tech aluminum Anodized matte black finish Includes two 3V CR123A batteries, Weaver ring, tripod mount,1"scope mount with adj. windage & elevation, remote momentary pressure switch, cleaning kit, hex wrench, lens cap & padded case *The patented Rotary Optical Collimator uses a system of 9 fully multi-coated lenses that allow full adjustment and control of the beam diameter and intensity to focus light where it's needed most. Rotating the collimator ring to minimum creates a bright micro-beam green laser light visible up to 3 miles. Rotating the collimator to more open settings provides plenty of illumination to light a trail at night or ôpaint"a target up to 400 yds. away. Attention: Do not stare directly into the laser beam or view directly with optical instruments. Viewing the laser light or a bright reflection may cause eye injury.