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Monstrum

Monstrum Guardian 3-9x50 AO Rifle Scope with Parallax Adjustment | Black

  • Based on 77 reviews
Condition: New
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$85.45 Why this price?
4th of July Sale · 34% off was $129.99

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Availability: In Stock.
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Arrives Monday, Jul 6
Order within 19 hours and 7 minutes
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Style: Guardian | 3-9x50 AO


Features

  • Adjustable 3-9 times magnification, for targeting out to 600 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 | 3-9x50 AO


Sport: Hunting


Item Weight: 15 Ounces


Material: Aluminum


Magnification Maximum: 9 x


Objective Lens Diameter: 50 Millimeters


Magnification Minimum: 3 x


Compatible Devices: Rifle


Magnification Maximum: 9 x


Objective Lens Diameter: 50 Millimeters


Magnification Minimum: 3 x


Compatible Devices: Rifle


Mounting Type: Weaver Mount


Night vision: No


Reticle Type: MOA


Item Weight: 15 Ounces


Item Display Weight: 15 ounces


Color: Black


Product Style: Guardian | 3-9x50 AO


Lens Color: Black


Brand Name: Monstrum


Sport Type: Hunting


Model Name: Guardian 3-9x50 AO


Manufacturer: Monstrum


UPC: 810088812002


Manufacturer Part Number: SG3950AO-B


Unit Count: 1.0 Count


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


Material Type: Aluminum


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Jul 6

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

    • Holds zero
Works great has good clarity and holds zero.
Reviewed in the United States on October 13, 2025 by Gunner
    • Perfect as described
Perfect scope for money
Reviewed in the United States on October 4, 2023 by George Schrom
    • If you're precise with the eye relief, it can be very accurate. If you're precise with the eye relief, it can be very accurate.
Review Image by BK
Clarity, eye relief, reaction to adjustment and light gathering ability are all pretty surprising for the price. While there is a large range of eye relief, about 80% of it is super sensitive to parallax variances. If you keep in the 20% sweet spot range, the accuracy is quite pleasant. I'm using it on a Hatsan Jet 1 in 22cal with round nose 16.08gr Dead Center pellets and with care, getting groups as shown above. This particular result was on the second of three magazines of seven at 25 yards. I first tried another budget scope and was horribly disappointed. ... show more
Reviewed in the United States on April 15, 2024 Reviewed in the United States on April 15, 2024 by BK
    • Monstrum Guardian rifle scope
I have a Rossi 30/30 R95 . This is the second scope I have bought from monstrum . It came with rings and mounted straight out the box . I used a wheeler engineering scope mounting tools now to get to the range
Reviewed in the United States on September 27, 2025 by Amazon Customer
    • Moa adjustment are not true.
This scope looks great, but IT WILL NOT HOLD ZERO! Will not adjust correctly. I bought this as a back up scope some time ago. Not sure if this is just from a bad batch. I will reach out to customer service to see what they will do.
Reviewed in the United States on September 28, 2025 by Martin
    • Good for old eyes
Works well on 22 cal Lever action.
Reviewed in the United States on September 15, 2025 by David 47
    • Outstanding scope
I mounded it on a 10/22 and it is perfect! Including the mounts
Reviewed in the United States on May 22, 2023 by Rick B.
    • Good optic
Put this on an AR-10, seems to hold up ok
Reviewed in the United States on November 5, 2024 by SMT

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