Holosun HS403GL Red Dot Sight

$180.00 USD

The Holosun brand has been introduced by a manufacturer that customarily has been an OEM for other brands. The manufacturer has now decided to market its own brand rather than relying on the OEM relationships.

The manufacturer has used its own R&D expertise to develop a red dot or reflex optic that is very compact, has extremely long battery life, clear optics, and a limited lifetime warranty.  The sight is designed to be compatible with aftermarket accessories designed for the market leader.  

NOTE:   A red dot or reflex sight utilizes a red light emitting diode to project a dot on the front objective of the optic so that when viewed through the eyepiece, the red dot is superimposed on the target.  This is not a laser sight that projects a beam on the target.


  • 50,000 hour battery life 
  • Low profile battery compartment on right side of sight
  • Mount is compatible with aftermarket accessories
  • Front Lens is angled to prevent glare
  • 2 MOA dot size  Unlimited field of view
  • Parallax-free with unlimited eye relief 
  • Unaffected by extreme weather conditions
  • Durable and reliable construction Lowest profile emitter on the market
  • Push button brightness setting
  • Auto shutoff after 8 hours
  • Auto awake to last setting with movement
  • Includes 1/3 co-witness AR riser
  • Weight: 114g (4.0 oz) including integrated mount
  • Working temperature: -10 °C to 50 °C (14 °F to 122 °F)
  • Storage temperature: -40 °C to 70 °C (-40°F to 158°F)
  • Objective diameter: 20 mm (glass), 28 mm (ring)
  • Limited Lifetime Warranty


Part No.


UPC 760921087503


Reflex collimator sight - red dot sight

Light source

LED (Light Emitting Diode) totally eye-safe wavelength: 650 nm red light

Red Dot Size

2 MOA -- 1 minute of angle = 30mm at 100 meters / 1.04 inch at 100 yards


Parallax free: No centering required, aim with red dot anywhere inside window.

Eye Relief


Night Vision

3 brightness setting for night version, Setting 1, 2, 3 is for night vision, From setting 4 to 12 are day time setting from dim to bright.


Multi-layer coating on all lens.





Battery Life

50,000 hours. Based on setting 6. Current is 5μA (micro Ampere). The battery capacity is 250mAHour. 250mAHoursX1000/5μA=50,000 hours

Auto Shutoff

8 Hours. After sight is not used for 8 hours, it will automatically shut off.


12 brightness setting include 3 night vision setting from 1 2 3. all setting current reading(from 12 to 1) 179μA 36μA 22μA 13.1μA 8.8μA 5.91μA 4.92μA 4.53μA 4.25μA 4.13μA 4.06μA 4.02μA

Housing Material


Housing Finish

PEO/MAO housing finish: Plasma electrolytic oxidation (PEO), also known as microarc 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 aluminium, 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.

Housing Color


Storage Temperature

-40°C to 70°C

Working Temperature

-10ºC to 50°C






Without integrated mount 86g (3.0 oz)

With integrated mount 114g (4.0 oz)

With 1/3 AR riser 140g (4.9 oz)