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// 29.9.2023 GA4 add to cart // 29.9.2023 GA4 add to cart

Holosun 503CU

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Holosun 503CU Details

About the Holosun 503CU

Holosun 503CU is a red dot sight of the Paralow series.

The letter 'C' means that the sight features a solar panel on top – the red dot sight can work without the battery inserted when there is sufficient lighting. The letter 'U' implies that the turrets of the device are shrouded and thus protected against potential blows.

The product features the ShakeAwake function. When left powered on, the sight will go from 'active mode' to 'sleep mode' after a while to prevent unnecessary battery drain. Once moved, it will power back on immediately.

Main features of 503CU MOA circle dot

  • circle dot reticle: 2 MOA dot & 2 MOA dot surrounded by a 65 MOA circle dot

  • comes with a low mount and a high mount for lower third co-witness on standard AR platforms

  • Holosun ShakeAwake function

  • a solar panel on top of the device

  • shrouded turrets

  • same mounting platform as Aimpoint Micro devices

  • 12 illumination intensity levels, 2 of them are NVD compatible

  • Parallax free

  • 50.000 hours of battery life

  • the battery compartment on the right side of the device in the form of a battery tray

About the Holosun Paralow series

Paralow is one of the red dot sight series made by Holosun. On the outside, these small tube sights are very familiar to the Micro red dot sights made by the famous Swedish red dot sight manufacturing company. The illumination is powered by a CR2032 battery. The click value for the elevation and windage adjustments is 0.5 MOA. These durable red dot sights feature a single-piece housing made out of aluminum. Altogether, there are 12 illumination intensity levels to choose from, 2 of which are NVD compatible. The battery life is 50.000 hours.

About the 503CU model family

Holosun 503 MOA red dot is one of the model families in the Paralow series. The first number '5' in its name suggests that the user can switch between a 2 MOA dot and a 2 MOA dot surrounded by a 65 MOA circle. The second number '0' implies that the product comes with standard accessories (without honeycomb filter, quick-release mount and flip-up lens covers).

Mounting details of 503CU MOA dot

These small tube sights come with a high mount for an AR platform (lower 1/3 co-witness) and a low mount for other mounting purposes (such as mounting on a rifle). All models in the Paralow series except the ones with the letter 'A' in their name have the same mounting platform as the Aimpoint Micro devices. For more information abput footprint on Holosun 503CU read our blog post Holosun 503CU Footprint

Warranty on Holosun red dot

The warranty on Holosun red dot is 3 years on the material and 3 years on the electronics.

For more information regarding the Holosun symbols, check our blog post.

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Holosun 503CU Specifications

Dot sight seriesHolosun Paralow
Made inChina
In production since2017
Warranty3 years
Click Value 14mm/100m - 1/2MOA
Windage - mrad. 14.53mrad
Windage - MOA.50MOA
Reticle2 MOA Dot, 65 MOA Ring
Reticle position No
Reticle illumination Yes
Usable at daytime Yes
Automatic Turn Off Yes
Size of Dot.2MOA
Adju. intensityYes
Intensity controlYes
Parallax setting Parallax-free
Length.66 mm
Width.36 mm
Height.41 mm
Working temperature range-30℃~60℃
Power Supply UnitCR2032
Battery lifespan.50000h
Filled with No
Lens coatings Fully Multicoated
Tube size/diameter 20 mm
Mounting StandardAimpoint Micro
Mount type - IntegratedFixed mount
Mount length.0mm
Size of windowNo
Dot Sight TypeSmall tube sight
Water proof Yes
Fogproof Yes
Shock proof501-1000 G
Type of mount rail Picatinny Mount


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Reviews & Testimonials

Reviews for Holosun 503CU

1 reviews
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Perfect. By
Probably best value for your money especially if you manage to find these on sale under 300€. There is basically nothing I would change on the sight. 0 distortion on the lens and with almost no tint at all. I don't know how you would be able to kill one of these, especially the models where the turret caps are shrouded. This model where the brightness is adjusted with buttons has slimmer housing than the ones that has the big knob on the side. Slimmer housing also means that, at least for me, when I superimpose the dot on a target, the optic housing almost completely disappears.

Durable and dependable, been using the sight in competitive shooting and even on a shotgun shooting 50g heavy loads and I have not seen the turrets lose zero or have any other problems.

(Posted on 07/12/2022)

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