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Monstrum

Monstrum Guardian Series AO Rifle Scope with Parallax Adjustment

  • Based on 1,331 reviews
Condition: New
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$94.95 Why this price?
Memorial Day Sale · 5% off was $99.95

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Availability: In Stock.
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Arrives Sunday, May 25
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Style: Guardian | 4-12x50 AO


Features

  • Adjustable 4-12 times magnification, for targeting out to 800 yards and beyond
  • An adjustable objective lens or AO - that allows for sharper focus of the target image, elimination of parallax, and range estimation
  • Aircraft grade 6061 aluminum scope body with a sealed, nitrogen-charged tube for resistance to water and fog
  • Precision 1/4 MOA/click windage and elevation adjustments with locking turrets
  • Package includes High Profile Picatinny/Weaver Scope Rings and set of flip-up lens covers

Brand: Monstrum


Color: Black


Style: Guardian | 4-12x50 AO


Sport: Hunting


Item Weight: 15 Ounces


Material: Aluminum


Magnification Maximum: 12 x


Objective Lens Diameter: 50 Millimeters


Magnification Minimum: 4 x


Compatible Devices: Rifle


Brand: ‎Monstrum


Color: ‎Black


Style: ‎Guardian | 4-12x50 AO


Sport: ‎Hunting


Item Weight: ‎15 Ounces


Material: ‎Aluminum


Magnification Maximum: ‎12 x


Objective Lens Diameter: ‎50 Millimeters


Magnification Minimum: ‎4 x


Compatible Devices: ‎Rifle


Mounting Type: ‎Picatinny Mount


Night vision: ‎No


Eye Relief: ‎3 Inches


Model Name: ‎Guardian 4-12x AO


Manufacturer: ‎Monstrum


Reticle Type: ‎Crosshair Reticle


UPC: ‎810088812026


Item Package Dimensions L x W x H: ‎15.98 x 3.39 x 3.03 inches


Package Weight: ‎0.94 Kilograms


Brand Name: ‎Monstrum


Part Number: ‎SG41250AO-B


Included Components: ‎Guardian Scope, One Pair High Profile Scope Rings, One Pair Spring-Loaded Flip-up Lens Covers


Date First Available: August 23, 2022


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, May 25

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

    • High quality at a great price!
Style: Guardian | 3-9x40 AO
We use Monstrum products almost exclusively in our shop for mounting scopes and optics.
Reviewed in the United States on April 25, 2025 by Alan Dodson
    • Good value
Style: Guardian | 3-9x40 AO
For a cheap scope option it's better than the rest. Highly suggest.
Reviewed in the United States on April 6, 2025 by Steven Harville
    • Good value
Style: Guardian | 6-18x50 AO
You can’t beat the price. After I read an article of the ten best scopes on Amazon I decided to get this one and visually it doesn’t disappoint. It wasn’t the top overall but my brother already had the one they voted #1 and I wanted to change it up. The rings that it came with has it sitting up a little high for my rifle but my rifle’s factory mounts were already high. I’m sure if you were using a picatinny rail it would be just right. As far as holding 0 I mounted it on a 6.5 creedmoor so……we’ll see. ... show more
Reviewed in the United States on March 4, 2025 by shay ulrich
    • Decent scope
Style: Guardian | 3-9x40 AO
Great scope, unfortunately it did not fit the rifle I bought it for,but that is not a reflection on the scope, but, I have another I can put it on. Or keep as a back hp.
Reviewed in the United States on February 26, 2025 by William
    • Es lo que buscaba
Style: Guardian | 3-9x50 AO
Buen material lo que se esperaba
Reviewed in the United States on March 13, 2025 by Juan figueroa
    • 6x18-50 scope seems to be good for the money.
Style: Guardian | 6-18x50 AO
Seems to be good for budget builds, just don't expect the same quality as premium scopes, but it seems to be worth the price. The iluminated reticle is ok, nothing special, but it does work. Optical quality is clear enough for range shooting. Bought it for my .17 WSM. Just needed something for around 250 yards, with a large objective to draw in more light, since the furthest berm at my range is in the shadows. Scope rings that come with it are meh, but will work for now. ... show more
Reviewed in the United States on December 6, 2024 by Nicklaus
    • My experiences
Style: Guardian | 6-18x50 AO
The scope came bagged up in an unsealed box with the illumination battery installed. No factory tape or indications on the carton , bag, or scope suggesting this was a new item, if it was inspected for quality at the factory or if this was a return put back into stock. It does work. At 50 and 100 yards with a pistol caliber AR platform rifle I was able to see my hits on a reactive (shoot n see) target. The eye relief is all or nothing. A very narrow window between decent clarity and a blurred mess. For what I want in an inexpensive scope for range plinking it works. No complaints. This is a rather large scope and on a pistol caliber AR platform rifle it may seem big for the rifle. ... show more
Reviewed in the United States on December 9, 2024 by Home Brew Audio
    • Sweet glass
Style: Guardian | 3-9x40 AO
Check most of the boxes after one takes into account it was $70.00 scope
Reviewed in the United States on February 16, 2025 by Shane Shier

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