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.
The 503 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).
Holosun 503 BU is a red dot sight of the Paralow series.
The letter 'B' means that the device has the battery compartment on the right side of the device in the form of a battery tray. Also, it lacks the solar panel, which is why this model has buttons for the regulation of illumination intensity on the top instead of on the side. 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 device will go from 'active mode' to 'sleep mode' after a while to prevent unnecessary battery drain. Once moved, it will power back on immediately.
2 MOA dot & 2 MOA dot surrounded by a 65 MOA circle
comes with a low mount and a high mount for lower third co-witness on standard AR platforms
same mounting platform as Aimpoint Micro devices
12 illumination intensity levels, 2 of them are NVD compatible
50.000 hours of battery life
the battery compartment on the right side of the device in the form of a battery tray
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.
The warranty is 5 years on the material and 3 years on the electronics.
For more information regarding the Holosun symbols, check our blog post.