Ultimate Arms Gear Tactical Marlin Rifle Rail Scope Sight Mount + 4x30 Dual Red & Green Illuminated Rangefinder Range Finder Reticle Rifle Hunting Sniper Tactical Scope Ultimate Arms Gear Marlin Rail Aircraft Grade Aluminum Alloy Mount with a Black Anodized Finish. Length: 4.73" . Complete with Screws & Allen Key for Mounting. Made to fit : Marlin 9, 45, 30AS, 30AW,36, 62, 93, 336, 336C, 375 & 444, 1993, 1894, 1895 Cowboy , Glenfield 30, Zane Grey & Camp-9 Carbine Marlin 922M & 989, Mossberg 640,Western Field 740. Easy to Install, Will Line Up with the Holes on your Rifle - If You Do Not Have the Predrilled Holes You Will Need to Get Your Rifle Tapped. Provides A Industry Standard 7/8" Weaver / Picatinny Tactical Rail for Attaching Accessories Such As Scopes, Sights, Optics, Flashlights, Scope Rings Etc. Black Anodized Aircraft Grade Aluminum. Accepts All Standard Weaver / Picatinny 1913 Accessories. Bolts Directly to Pre-Drilled and Tapped Flat Top Receiver. Magnification- 4X Fixed. Crystal Clear 30mm Lens . Tube Diameter- 1". Illuminated Red - Green Rangefindier reticle : 11 different illumination settings (1 -Black when not illuminated, 5-illuminated red ,5 illuminated green). Full Windage and Elevation Adjustments. Nitrogen Filled, Shockproof, Fogproof, and Water Resistant.