GUIDE TK421 400×300 25 mm thermal monocular is a well-balanced mid-range thermal imaging device designed for mobile observation, patrol, perimeter security, and tactical applications in low-visibility conditions. It features a 400×300 VOx sensor with a 17 µm pixel pitch, a fast 25 mm F/1.1 lens, and provides human detection at distances of up to 1700 meters. With a 50 Hz refresh rate, wide magnification range, and built-in Wi-Fi, the device performs well in dynamic operational scenarios.

🫡 We are a team of veterans

We are a team of veterans evaluating thermal devices from a practical, field-oriented perspective. GUIDE TK421 is seen as a versatile solution where image clarity, stability, and sufficient detection range are required without excessive weight or size. It is a reliable tool for patrol and security tasks.

⚙️ Specifications

Parameter	Value
Device type	Thermal monocular
Sensor	VOx 400×300
Pixel pitch	17 µm
Refresh rate	50 Hz
NETD	<50 mK
Objective lens	25 mm F/1.1
Optical magnification	1.7×
Maximum magnification	6.8×
Display	1280×960, LCOS
Human detection range	up to 1700 m
Interfaces	Wi-Fi
Power source	18650 battery
Battery capacity	6000 mAh
Operating time	up to 5 hours
Protection rating	IP66
Dimensions	192×71×65 mm
Weight	470 g

💬 Comment

GUIDE TK421 sits between compact short-range models and heavy long-range thermal imagers. The 25 mm lens offers a strong balance between field of view and detection range, while the 400×300 sensor provides improved detail over entry-level devices. It is well suited for continuous mobile use.

🎯 Who it is for

Primarily for military personnel performing patrol and observation duties at medium ranges.
For security and territorial defense units requiring a versatile night observation tool.
For hunters seeking a balance between detection range and portability.
For search and rescue or volunteer teams operating at night who need stable imaging and reliable performance.

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Thermal imager monocular GUIDE TK421 400x300px 25mm

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SKU: 3664

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$1 390

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