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Customer Reviews
Helpful Positive Review
Monstrum Optics by Rod Dobber, Verified Owner, October 3, 2024
This is a good scope for a budget build. Clear glass, adjustments work well, and it functions like a more expensive optic.
1/1 found this helpful
Helpful Positive Review
Solid scope for the price by MT Lee, Verified Owner, July 13, 2024
Good value for a scope. 4 to 5 inch eye relief. Good clarity, not too heavy. Zoom ring is stiff until used a bit, but it gets easier. The reticle is a nice thin hash marked cross that can be illuminated green or red. I have a few of these Monstrum Gu...
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1/1 found this helpful
Helpful Positive Review
Monstrum Scope by Rod Dobber, Verified Owner, November 8, 2024
I recently ordered a Monstrum scope. It isn’t a top of the line optic in terms of dollars, but it functions as a top of the line optic. It zeroed in the rifle I put it on with just a few shots. The glass is clear and the controls work well. I have n...
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1/1 found this helpful
Most Recent Reviews
Monstrum scope by Michael, Verified Owner, December 17, 2025
Great piece of hardware, clear, optics, durable waterproof, and all the good stuff but highly Recommend two hunters
Most Recent Reviews
affordable by jackson, Verified Owner, March 2, 2024
I own 3 of these and they are sufficient for me to hunt or target practice. 2 are on 300 bo ar pistol and 1 on 223 wylde ar pistol. Cant imagine spending more to no get much more. I would recommend to anyone hunting or plinking.
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Eligible models will have a savings offer. Apply coupon and add the item to your cart for savings on that select model! Limited time only. Cannot be combined with other promotions or offers. See promotion details.
Reticle: Crosshair Tube Diameter: 1 inReticle Focal Plane: Second Focal Plane (SFP) Illumination Color: Red Finish: Anodized Color: Black Weight: 14 ozAdjustment Click Value: 1/4 MOAAdjustment Type: MOA Condition: New

Code: MON-RS-AO9B3-SG3940-B

MPN: SG3940-B

UPC: 810088810787

15%
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List: $69.95Save 14%
$59.99

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Product Info for Monstrum Guardian 3-9x40mm 1in Tube Rifle Scope, Second Focal Plane

The Monstrum Guardian Series is the latest iteration from Monstrum best selling line of SFP rifle scopes! The Guardian 3-9x is a full-featured scope suitable for hunting, target shooting, or tactical use. Fully illuminated MOA reticle with MOA hashmarks for ranging information and inline dial controlled brightness adjustments. Precision 1/4 MOA/click windage and elevation adjustments. Anodized aircraft grade 6061 aluminum construction, for lightweight and durable performance. An integrated throw lever for smooth and controlled adjustment of the magnification dial.image

Specifications for Monstrum Guardian 3-9x40mm 1in Tube Rifle Scope, Second Focal Plane:

Manufacturer: Monstrum
Objective Lens Diameter: 40 mm
Magnification: 3 - 9 x
Reticle: Crosshair
Tube Diameter: 1 in
Reticle Focal Plane: Second Focal Plane (SFP)
Illumination Color: Red
Finish: Anodized
Eye Relief: 3.5 - 3.8 in
Color: Black
Weight: 14 oz
Adjustment Click Value: 1/4 MOA
Length: 14 in
Adjustment Type: MOA
Battery Type: CR2032, Lithium Metal
Fabric/Material: 6061 Aircraft-Grade Aluminum
Focus Range: 500 yds to infinity
Lens Material: Glass
Battery Life: 50,000 hours
Weather Resistance: Fog Resistant
Water Resistance Level: Waterproof
Fogproof: Yes
Battery Quantity: 1
Condition: New
Attachment Type: Picatinny
Mount Type: Picatinny
Fit: Rifles

Features of Monstrum Guardian 3-9x40mm 1in Tube Rifle Scope, Second Focal Plane

  • Scope Range: Close to Mid Range, 500+ Yards

Package Contents:

  • Monstrum Guardian 3-9x40mm 1in Tube Rifle Scope, Second Focal Plane
  • Offset Scope Mount
  • Lens Cloth
  • Lens Cover

Monstrum Guardian 3-9x40mm 1in Tube Rifle Scope, Second Focal Plane Orderable Models

List of Orderable Models

  • Monstrum Guardian 3-9x40mm 1in Tube Rifle Scope, Second Focal Plane, Crosshair Reticle, Black, SG3940-B , MPN: SG3940-B , UPC: 810088810787 , Code: MON-RS-AO9B3-SG3940-B

Monstrum Guardian 3-9x40mm 1in Tube Rifle Scope, Second Focal Plane Unavailable & Discontinued Models

List of Unorderable Models

  • USED Monstrum Guardian 3-9x40mm 1in Tube Rifle Scope, Second Focal Plane, Crosshair Reticle, Black, SG3940-B, EDEMO1, Condition Fair, Used , MPN: SG3940-B-EDEMO1 , Code: MON-RS-AO9B3-SG3940-B-EDEMO-US-D
  • USED Monstrum Guardian 3-9x40mm 1in Tube Rifle Scope, Second Focal Plane, Crosshair Reticle, Black, SG3940-B, EDEMO2, Condition Fair, Other , MPN: SG3940-B-EDEMO2 , Code: MON-RS-AO9B3-SG3940-B-EDEMO-OT-D
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