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Monstrum

Monstrum Guardian 6-18x50 AO Rifle Scope with Parallax Adjustment

  • Based on 167 reviews
Condition: New
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Availability: In Stock.
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Arrives Saturday, Oct 17
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Color: Black


Features

  • Adjustable 6-18 times magnification, for targeting out to 1000 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

Description

The Monstrum Guardian Series of precision SFP rifle scopes provides crystal clear optics with variable power options of 3-9x, 4-12x, and 6-18x based on model selection. This makes it ideal for a wide variety of applications such as hunting and long-range applications. The adjustable objective bell allows for parallax adjustment to obtain a sharp target at any distance. The glass-etched crosshair reticle features 1 MOA per tick and 10 MOA per grouping with a total of 80 MOA per axis. The entire reticle illuminates in 5 levels of red and green for visibility in most environments.

Brand: Monstrum


Color: Black


Style: Tactical


Sport: Hunting


Item Weight: 15 ounces


Material: Aluminum


Magnification Maximum: 18 x


Objective Lens Diameter: 50 millimeters


Magnification Minimum: 6


Compatible Devices: Rifle


Magnification Maximum: 18 x


Objective Lens Diameter: 50 millimeters


Magnification Minimum: 6


Compatible Devices: Rifle


Mounting Type: Picatinny Mount


Reticle Type: MOA


Item Weight: 15 ounces


Item Display Weight: 15 ounces


Color: Black


Product Style: Tactical


Lens Color: Black


Material Type: Aluminum


Brand Name: Monstrum


Sport Type: Hunting


Number of Packs: 1


Model Name: Guardian 6-18x AO


Manufacturer: Monstrum


Number of Items: 1


Unit Count: 1 Count


UPC: 810088812040


Manufacturer Part Number: SG61850AO-B


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Oct 17

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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Similar Products

Top Amazon Reviews

    • MONSTRUM ALWAYS PROVIDES QUALITY AT AN EASILY AFFORDABLE PRICE!
Color: Black
My Monstrum Guardian Series AO Rifle Scope with Parallax Adjustment, is a Second Focal Plane scope (my preferred Focal Plane for long-range shooting [750yds+]). The glass is perfect (clear, sharp presentation of illuminated crosshairs, and no halo or fog), and the 1" tube is solid and well made. The 1/4 MOA/click windage and elevation adjustable turrets have screw-on covers to keep your adjustments secure once zeroed, and the clicks are smooth and positive. I have a couple of scopes costing 10 times more than the Monstrum Guardian Series AO Rifle Scope, and I bought it "just to check it out" because of the low-end price. I have used several Monstrum cantilever mounts, and other Monstrum products which impressed me enough to try their optics, and the Monstrum Guardian Series AO Rifle Scope with Parallax Adjustment surpassed my expectations. Monstrum provides an outstanding scope at a bargain price in the 6-18 power range. You are reading this review, and I have NO association with Monstrum other than as a customer, so if you're looking for a 6-18 variable optic, I STRONGLY recommend the Monstrum Guardian Series AO Rifle Scope! If you don't like it and bought it from Amazon, you can return it for credit or replacement. ... show more
Reviewed in the United States on December 5, 2023 by Gil
    • Impressive glass
Color: Black
The construe parallax rifle scope I purchased exceeded my expectations in terms of optical clarity and precision. The parallax adjustment feature allows for crisp, distortion-free target acquisition at various distances. The scope's build quality is robust, and the turrets provide tactile and audible feedback, ensuring easy and accurate adjustments. Whether for hunting or precision shooting, this parallax rifle scope delivers consistent performance. The only minor downside is the relatively higher price point, but the optical quality and build justify the investment for enthusiasts seeking top-notch accuracy in their shooting experience. ... show more
Reviewed in the United States on January 18, 2024 by GS
    • Decent Rifle Optic
Color: Black
Trying to find an optic for a small caliber rifle, I stumbled upon this Monstrum Guardian 6-18x50, and decided to give it a go. About half the price of a Bushnell in the same zoom range. Included rings to mount it. Took it to the range, and I'm still not completely sold. Eye relief is decent, rings are very basic, but seem to hold. Optic caps are a nice touch, but get in the way for making focal adjustments (being they are flip ups). Not sure how to properly gauge it, but I'm doubting the 18x zoom is accurate. When compared to a vortex 12x, with 50mm objective lens, the zoom appears almost less. Still a functional small caliber option, just don't believe the zoom rating. ... show more
Reviewed in the United States on July 14, 2023 by B. Peterson
    • Super nice
Color: Black
Very nice scope for the price. Easy to sight in. Feels very high quality.
Reviewed in the United States on March 24, 2026 by Emalee Grant
    • Phenomenal
Color: Black
I am truly a fan of Monstrum Optics. Don’t let the price fool you on this one=an inexpensive scope does not mean cheap. The optic is crystal clear the cross hair and illumination is perfect. It allows the choice of red or green cross hairs. The parallax adjustment is spot on. I zeroed my AR 5.56 at 100 yards with a sub moa group-sub moa ! I have a couple good optics -ACOG, Holosun, Trijicon and this Monstrum performs just as well. The optic adjustments have distinct feel /clicks 1/4 moa. I like this scope a lot! ... show more
Reviewed in the United States on May 21, 2024 by Thomas Glapion
    • My experiences
Color: Black
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
    • 6x18-50 scope seems to be good for the money.
Color: Black
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
    • A++
Color: Black
And then some !!!
Reviewed in the United States on September 17, 2026 by Mario Melgar

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