Holosun hs515c - Holosun Paralow HS503C Circle Dot Sight

My purchase was actually the Holosun 515C, not the 503C. The difference is that in addition to all of the 503C's features, the 515C also has a Quick Detach base, a "Kill Flash" on the front lens, and hinged lens caps instead of rubber bikini covers. The front and rear tubes are a little longer to accommodate the lens cover attachment, and the covers hinge down, rather than up where they could be easily snagged and broken.

The "Kill Flash" is a grid over the front lens that prevents or reduces reflections back toward the target.

The Quick Detach base lever locks, requiring a push on a button to release, so it is not easily snagged and opened.

At the range it was easy to zero, tracking adjustments well. Turning off the reticle's circle, leaving only the dot, and using the manual mode to turn the dot brightness down as much as possible seemed to reduce the size of the dot for more accuracy for zeroing on the target.

Overall, I'm very impressed with these sights, especially the HS515C.