The Osight SE is a versatile enclosed dot sight featuring a crisp 2 MOA red dot and a 32 MOA circle, which can be used individually or together for fast and precise aiming. Compared to its predecessors, the Osight SE uses an easily replaceable battery, so you're always ready to go without waiting for a charge or dealing with the hassle of a charging cover. The Osight SE offers 10 brightness settingstwo optimized for night vision and eight for daytime use. The aspherical lens provides zero distortion and parallax-free performance, delivering exceptional clarity through the large window for quick target acquisition. The optic is easy to zero with both windage and elevation adjustments, ensuring consistent accuracy. The Osight SE also includes a motion sensor that activates with movement and powers down after 3 minutes of inactivity (this feature can be disabled if desired).Powered by a CR1620 battery, the Osight SE offers up to 75,000 hours of runtime in dot-only mode at the lowest daytime brightness. When its time to replace the battery, the reticle blinks three times every minute to indicate the need for a swap. To replace it, simply unscrew the side battery housing and pull out the side battery loader for quick access. Compact and lightweight, the Osight SE measures just 1.59 inches in length and weighs only 0.97 ounces, keeping a low profile. With an IPX7 waterproof rating and a durable 7075 aluminum housing, its built to deliver reliability and toughness in any environment. Specifications for Osight SE 1x 21x14mm Reflex Red Dot Sight: Manufacturer: Osight Color: Black Fabric/Material: 7075 Aluminum Magnification: 1 x Objective Window Size: 21x14 mm Reticle: 2 MOA Dot, 32 MOA Circle Illumination Type: LED Illumination Color: Red Brightness Settings: 10 Eye Relief: Unlimited Adjustment Click Value: 1 MOA Emitter Type: Enclosed Parallax: Parallax Free Battery Type: CR1620 Operating Temperature: -30 - 70 Celsius Water Resistance Level: IPX-7 Length: 1.59 in Width: 0.98 in Height: 0.97 in Red Dot Sights-Footprint: RMSc Features of Osight SE 1x 21x14mm Reflex Red Dot Sight Features a red 2 MOA dot and a 32 MOA circle Features 10 brightness settings: 2 for night vision, 8 for daytime use Activate the motion sensor function to turn on the optic with any movement Easy removable battery so you don't have to rely on charging Package Contents: Osight SE 1x 21x14mm Reflex Red Dot Sight Adjustment Tool 3 x M310.5mm Screw 3 x M311.5mm Screw 3 x M49.4mm Screw 3 x M410.5mm Screw 3 x #6-320.433 in Screw 3 x #6-400.374 in Screw 3 x #6-400.449 in Screw 2 x Battery Compartment Screw Screw Box Cleaning Cloth