Fortuna General Clip-On 40A6 product image

Fortuna General Clip-On 40A6

The GENERAL CLIP-ON 40A6 is a thermal clip-on made by Fortuna and is part of the General Clip-On series.


The General Clip-On 40A6 comes with a quality 40mm f/1 lens to capture thermal signatures. The FOV on this thermal clip-on reads 15.2 x 11.5 degrees.

Inside the housing of the General Clip-On 40A6 you'll find the (uncooled, 17µm) 640 by 480px thermal imaging sensor with a refresh rate of 25Hz. The NETD (Noise Equivalent Temperature Difference) of this thermal clip-on is <50mK and it's operating between the 7.5µm and 14µm wavelengths.

The dimensions of this thermal clip-on are 60 x 70 x 168mm (length/width/height) and weighs 470g. This device is rated IP67. It can withstand dust, shocks, water (splashes) and submersion under water. Operating temperatures range between -30°C and 50°C.

The General Clip-On 40A6 is suitable for hunting, law enforcement and the military.



  • Durable aluminum rubberized body
  • Compact and light-weight
  • User-friendly digital menu
  • Suitable for 3-15x daylight scopes
  • Quick release mount


Lens40 mm
Optical zoom1 x
FOV (h/v)15.2 ° / 11.5 °
Focus range10m to infinity
Thermal typeUncooled
Sensor resolution (h/v)640 pixels / 480 pixels
Pixel pitch17 µm
Sensitivity50 mK
Spectral range7.5 µm / 14 µm
Display resolution (h/v)800 pixels / 600 pixels
Refresh rate25 Hz
Output screen colorFull color
Dimensions (l/w/h)60 mm / 70 mm / 168 mm
Weight470 g
Number of batteries2
Battery life5 hours
Operating temperature-30 °C / 50 °C
Environmental ratingIP67
Law enforcement
Search & rescue
Fire fighting

DRI Ranges

DRI stands for Detection, Recognition and Identification and is based on the widely used Johnson's criteria.

  • Detection Detect if an object is present
  • Recognition See what type of object it is (i.e. person, vehicle, airplane)
  • Identification For example see if someone is a friend or foe
Detection Recognition Identification
Rabbit 423 meters 105 meters 52 meters
Person 1490 meters 372 meters 186 meters
Vehicle 3607 meters 901 meters 450 meters

Please note that these values are calculated, always consult the manufacturer for official range numbers.


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 Fortuna General Clip-On
 Fortuna General Clip-On
 Fortuna General Clip-On
 Fortuna General Clip-On
 Fortuna General Clip-On
 Fortuna General Clip-On
 Fortuna General Clip-On


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