Monstrum Ruckus Prismatic Red Dot Sight w/ Shake Awake 3x30mm Circle Dot Reticle Black. Activate the illumination to turn on shake awake mode - the dot will automatically shut off after ten minutes and re-activate instantly upon movement. Prism scope reticles are etched in glass produces less distortion than red dots and are easier for the eye to focus on especially for shooters with astigmatism. Available in three different reticle options: the BDC reticle the Circle Dot retcle and the DX1 reticle. All Monstrum products are backed by a full lifetime warranty Specifications for Monstrum Ruckus 3x30mm Prismatic Red Dot Sight w/ Shake Awake: Manufacturer: Monstrum Color: Black Magnification: 3 x Objective Lens Diameter: 30 mm Illumination Color: Red Battery Type: Lithium Metal CR2032 Weight: 17 oz Red Dot Sights-Footprint: Not Applicable Package Contents: Monstrum Ruckus 3x30mm Prismatic Red Dot Sight w/ Shake Awake Monstrum PK3XB-CIR: Ruckus Prismatic Red Dot Sight w/ Shake Awake 3x30mm Circle Dot Reticle Black