Holosun HS403A Micro Red Dot

Holosun Technologies Inc. has been an Original Equipment Manufacturer (OEM) for several years for many brands that you may be familiar with.  This includes both components and ready to sell full sight systems.  With this relationship, has come an accomplished team of engineers, research and development members and manufacturing expertise.  Holosun has decided to build unique red dot / reflex sights under their own brand at a very competitive price.

Technologies to Note:

1. 50,000 hour battery life. You have already seen technology like this with more expensive sights.   They uses techniques like pulsing the Light Emitting Diode (LED) to save power.  Holosun has obtained the same battery life using their own proprietary technology but with a continuously on LED.  The result is a sharper red dot. High quality CR2032 lithium cells, like the one supplied with Holosun sights have a capacity of 240 – 250 mAh (mili-Ampere Hours).   At brightness level 6, the sight uses 4.92μA (micro-Amperes).  Even without the other power saving features, this represents 50,000 hours of continuous operation.  The measured current for each brightness level can be found in the specifications.  Even at the maximum brightness level, the current draw of 179 μA still yields 1390 hours of operation.  Still years of use at a couple of hours a day.  The newest circle-dot reticle sights are able to have a battery life in excess of 30,000 hours.
2. Automatic power off.   The HS403A and HS403G are designed to automatically power off the sight after 8 hours of inactivity.  A slight vibration of the sight turns the red dot back on.  This timing is adjustable from 2 – 8 hours.  With normal use, this effectively extends the battery life to the shelf life of the battery.  This also makes this sight a perfect for operating in low light situations so it will power on when you need it, without having to fumble with controls.  There is also another benefit.  Most folks don’t know that an LED has a finite life.  Even if a manufacturer says their LEDs have a life of 50,000 hours, a common number, many won’t tell you that this is to the point of 50% of original specification intensity.  The automatic power off feature extends the life of the LED itself as well as all of the electronics in the sight.
3. Battery in base (HS403A).  With the extended battery life, Holosun was able to mount the battery in the base of the sight since you will only rarely need to replace the battery.  This makes for a very compact sight and assists with eyes both open shooting.  Some models also use either a low profile external battery compartment or a battery tray.
4. Optics.  Holosun has taken their engineering expertise to develop a very bright and low parallax optical system.  Parallax can affect your point of impact based on the position of your eye with respect to the central axis of the sight.  Parallax should never exceed 10mm (.4”) or half the diameter of the objective lens.  This means that at 30 meters (33 yards), there is no apparent parallax.  Many sights at this price point will say they are parallax free but only beyond 50 yards.
5. MOA finish.  PEO/MAO housing finish: Plasma electrolytic oxidation (PEO), also known as micro-arc oxidation (MAO), is an electrochemical surface treatment process for generating oxide coatings on metals. It is similar to anodizing, but it employs higher potentials, so that discharges occur and the resulting plasma modifies the structure of the oxide layer. This process can be used to grow thick (tens or hundreds of micrometers), largely crystalline, oxide coatings on metals such as aluminum, magnesium and titanium. Because they can present high hardness and a continuous barrier, these coatings can offer protection against wear, corrosion or heat as well as electrical insulation.  

SPECIFICATIONS