Night vision binocular D221B is a professional night vision device designed to perform various activities in low-light conditions, which require to detect and recognize moving and fixed objects located at a considerable distance (up to 900 meters). Binocular arrangement of the device and special optics provide high-quality stereoscopic image, which leads to greater recognition distance 1.3-1.5 times, compared to devices which use a pseudo binocular scheme. Design enables to use tubes gen. 2+/3 of leading world manufacturers.
The device is made in the waterproof version, has a possibility of filling with nitrogen, built-in dehydration cartridge prevent s defogging of lenses inside when unforeseen depressurization.
Night vision binocular D221B features:
- body from light alloys of alluminium;
- switch-off indicator;
- built-in IR illuminator and possibility to install additional powerfull IR illuminator;
- filling with dry air or nitrogen;
- cartridge of dehydrator;
- high quality stereoscopic image that ensures the increase in distance of detection and recognation up to 1.3-1.5 times, compared with the devices which apply pseudo binocular
- possibillity to install an additional IR-illuminator (laser or diode) in special slot to increase the distance of detection and recognition considerably. 
- possibillity to install 2 types of lenses to get the magnification of 3,1x or 4,6x. 

Tube, generation 2+ 2+
Lenses, focal length, mm F80/1.5 F120/2.0
Magnification 3.1x 4.6x
Focus limit, m 5 ... ∞ 15 ... ∞
Angle of vision, degr 12 8
Diopter adjustment, dptr ± 4 ± 4
Interpupillary distance, mm 64±4 64±4
Supply voltage/type of batteries 3V/ CR123A 3V/ CR123A
Operating time (without IR), hour 48 48
Built-in IR illuminator: type/ wavelength/ power diode/ 805/ 40 diode/ 805/ 40
Operating temperature range, °C (with remote source) -10...+50 (-30...+50) -10...+50 (-30...+50)
Detection range (object 0,5х1,8m; light exposure 5х10-3lux), m
- 2+ gen up to 550 up to 680
Degree of protection according to IEC 60529 (by order) IPX5 (IPX7) IPX5 (IPX7)
Dimensions, mm 185 x 122 x 64 260 x 127 x 67
Weight, kg 1.12 1.36