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Monstrum 3-12x42 AO Rifle Scope with Illuminated Mil-Dot Reticle and Offset Reversible Scope Rings

  • Based on 237 reviews
Condition: New
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Availability: In Stock.
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Arrives Friday, May 24
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Features

  • Adjustable 3-12 times magnification, for targeting out to 500 yards and beyond
  • Adjustable reticle illumination with 5 brightness levels in both red and green, allowing for better reticle visibility in low light environments
  • An adjustable objective lens or AO - that allows for sharper focus of the target image, elimination of parallax, and range estimation
  • A mil-dot reticle with markings that allows you to estimate range or compensate for bullet drop
  • Aircraft grade 6061 aluminum scope body with a sealed, nitrogen-charged tube for resistance to water and fog

Brand: Monstrum


Color: Black


Sport: Hunting


Item Weight: 1.4 Pounds


Material: 6061 Aircraft Grade Aluminum


Magnification Maximum: 12 x


Objective Lens Diameter: 50 Millimeters


Magnification Minimum: 3 x


Compatible Devices: Rifle


Mounting Type: Picatinny Mount


Brand: ‎Monstrum


Color: ‎Black


Sport: ‎Hunting


Item Weight: ‎1.4 Pounds


Material: ‎6061 Aircraft Grade Aluminum


Magnification Maximum: ‎12 x


Objective Lens Diameter: ‎50 Millimeters


Magnification Minimum: ‎3 x


Compatible Devices: ‎Rifle


Mounting Type: ‎Picatinny Mount


Night vision: ‎Yes


Item Package Dimensions L x W x H: ‎16.5 x 5.31 x 3.19 inches


Package Weight: ‎1 Kilograms


Brand Name: ‎Monstrum


Manufacturer: ‎Monstrum


Part Number: ‎S31242-M-RG-AO


Included Components: ‎3-12x42 SFP LPVO Scope, 1 inch Medium Profile Offset Scope Rings, 1x CR2032A Battery, Lens Cleaning Cloth, Manual


Date First Available: October 27, 2014


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, May 24

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Very Good Scope
Color: Black
This has been a very good scope, especially at the price point. It is just as nice as higher priced scopes. Like other reviewers, I did find my zoom to be stiff, but after turning it a few times, it works beautifully. I had never heard of this company before, but decided to take a chance and have been very happy. It took me 6 shots to zero in and after 200 rounds, held zero. I have had no problems. ... show more
Reviewed in the United States on November 1, 2019 by John W

  • It is a reasonably priced, budget scope.NOT a $700 scope.
Color: Black
Eye relief is not great.Parralax is off (by 7 yds)but smooth.There is a set screw which seems to be able to loosen and perhaps line up the turret if you used it for range estimation in the field.IR is bright so it does halo.(I just left it on a while and it dimmed to a tolerable level after the battery depleted slightly.)Overall pleased.Nice and compact.It is on a PCP air rifle so I cannot attest to it's sensitivity in the recoil arena. ... show more
Reviewed in the United States on June 7, 2023 by M.White

  • Clear vision
Color: Black
I like the lens caps reticle lights up good magnification dial lilstiff but moves all good
Reviewed in the United States on August 26, 2023 by pewpewpew

  • Nice!!!
Color: Black
Minor quibbles: the side AO markings are not accurate. At 25 yards, the dial has to be turned to about 15 yards. The fact that the yardage markings are off does not bother me so much as the fact that my scope does not actually focus down the the 7.5 yards as indicated on the dial. The minimum distance my scope focuses clearly is about 10-12 yards. Another minor complaint is that the light up reticle is too bright at the lowest setting. And there's a bit of bright halo/ring visible. Great scope for the money. Satisfied with the optics and performance. ... show more
Reviewed in the United States on March 27, 2022 by Shooter McGavin

  • Stacks up with Vortex In my opinion!!
I have been a vortex loyal guy for years now because of the quality of optic you get for the money is unbeatable! As I will always be a vortex guy, I am now also a MONSTRUM TACTICAL guy! This is my first monstrum scope and it is so crisp, tight, and precise it had me double checking the name on the side of the scope when I took it out of the box because I’ve never seen a scope that solid for the amount of money I paid. On top of that the people from MONSTRUM Tactical have followed up with me since I received my scope to ensure I was 100% satisfied with their product and there were no issues. I want to add that it wasn’t just one of those emails fishing for a good review so they could make more money. The email MONSTRUM sent to me expressed a genuine concern that this company wants to make sure they are supporting their customers in every way possible and they are giving people a quality product for their hard earned money. I’m already planning the one I’m buying next. ... show more
Reviewed in the United States on May 25, 2019 by Mikey Price Mikey Price

  • Index marker hard to see
Just got my 3-12 scope. Zoom ring not as stiff as others have said. The parallax numbers are hard to read and the index marks for it and zoom are hard to see. My scope is the FDE model. Have not taken out to shoot with but the glass is clear in both day and night. At night, the scope gather light well. The reticle is easy to pick up and mil dots seem easy to use. Wish there is a Kill Flash option but the objective lens is threaded. It did come with a spare battery. Windage and elevation knobs are positive with audible clicks, can be reset to zero but you need to use own hex key since the one provided is for use on the scope rings. Did not use the scope rings but they do seem to sturdy. Looking forward to trying it out and see how well it holds zero on ruger ranch rifle 5.56. ... show more
Reviewed in the United States on June 23, 2020 by Joseph T.

  • But something else
Seemed great, installed...looked nice. Turned on the green and awesome...turned on the red and one side was burnt out. Unfortunately this one is headed back. Moving onto a Vortex.
Reviewed in the United States on April 18, 2020 by Chris Miley

  • Good Scope for the money
Color: Black
Wanted a economically priced scope for my coyote / target range fun gun was concerned having never heard of Monstrum tactical before . scope showed up very quickly ,glass is very clear was easy to sight in . 1 range session with about 50 rounds so far pretty good
Reviewed in the United States on October 20, 2019 by TomD

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