<div style="background-color:#dae4ea; border: 1px solid #648798; padding: 10px;"><b>Product no longer available. Have you checked out its successor?<br/>Why not enjoy the benefits that it has to offer:<br/> <a href="…/p/0636-9772">>> To the product (fixed cable)</a><br/> <a href="…/p/0636-9771">>> To the product (wireless, with Bluetooth)</a><br/>Please note that the successor products are only compatible with testo 400 or testo 440.</b></div>

For measurements in cleanrooms and laboratories, and critical processes in the pharmaceutical, industrial and food sectors, as well as in storage, refrigerated and work rooms or in air conditioning/ventilation ducts: use the high-precision humidity/temperature probe (with the compatible measuring instrument) to measure relative humidity and air temperature. The readings are transmitted directly to your measuring instrument via Bluetooth, making your measurements particularly convenient.

For measurements in cleanrooms and laboratories, and critical processes in the pharmaceutical, industrial and food sectors, as well as in storage, refrigerated and work rooms or in air conditioning/ventilation ducts: use the high-precision humidity/temperature probe (with the compatible measuring instrument) to measure relative humidity and air temperature.<br />&nbsp;

More applications, less equipment: if you already own one of our probes with a universal handle, you can easily expand your portfolio of probes with the high-precision humidity/temperature probe head.

For measurements in storage, refrigeration and work rooms, in ventilation ducts and also on refrigeration systems and heat pumps: use the humidity/temperature probe (with the compatible measuring instrument) to measure relative humidity and air temperature.

For measurements in storage, refrigeration and work rooms, in ventilation ducts and also on refrigeration systems and heat pumps: use the humidity/temperature probe (with the compatible measuring instrument) to measure relative humidity and air temperature. The readings are transmitted directly to your measuring instrument via Bluetooth, making your measurements particularly convenient.

The ideal probe for measuring the humidity and temperature of the air in storage, refrigerated and work areas, as well as in air conditioning/ventilation ducts. Also suitable for long-term measurements.

More applications, less equipment: if you already own one of our probes with a universal handle, you can easily expand your portfolio of probes with the humidity/temperature probe head.

For measurements in industrial exhaust air, in bulk materials and in climatic test cabinets: use the robust humidity/temperature probe (with the compatible measuring instrument) to measure relative humidity and air temperature up to +180&nbsp;&deg;C.<br />&nbsp;

The high-quality testo 315-3 is an easy-to-use, ruggedly designed CO and CO<sub>2</sub> meter that enables you to carry out quick and reliable ambient measurements according to DIN EN 50543 standard.

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For quick, precise measurement of carbon monoxide in ambient air &ndash; in accordance with DIN EN 50543: The testo 315-4 CO measuring instrument is easy to operate, has a robust design and is of durable quality.<br /><br />&nbsp;

<div style="background-color:#dae4ea; border: 1px solid #648798; padding: 10px;"><b>Product no longer available. Have you checked out its successors?<br/>Why not enjoy the benefits that they have to offer: <a href="https://www.testo.com/multifunction">>> To the products</a></b></div>

Kit for carrying out measurements in storage, refrigeration and work rooms, in ventilation ducts and also on refrigeration systems and heat pumps. Keep the testo 440 air velocity and IAQ measuring instrument and the humidity/temperature probe with Bluetooth<sup>&reg;</sup> safely stowed away in the case. So you can get down to work straight away!

Carry out measurements without any annoying cables: use the kit to handle all relevant measurements in ventilation ducts and at air/ceiling outlets. You will receive the testo 440 dP air velocity and IAQ measuring instrument including differential pressure sensor, two vane probe heads (Ø 100 mm and Ø 16 mm) and a humidity/temperature probe head – all three can be attached to the universal Bluetooth<sup>&reg;</sup> handle supplied. To make measurements more convenient, both vane probe heads can be combined with the telescope included in the kit. The equipment can be transported safely and conveniently in the robust case.

You can keep a close eye on indoor air quality with the testo 445 climate measuring instrument: the allrounder can measure up to 6 parameters (with the appropriate probe), which can help you make a professional assessment of indoor air quality. The climate measuring instrument therefore supports you in adjusting and checking ventilation and air conditioning systems.

<div style="background-color:#dae4ea; border: 1px solid #648798; padding: 10px;"><b>Product no longer available. Have you checked out its successor?<br/>Why not enjoy the benefits that it has to offer: <a href="…/p/0563-1625">>> To the product</a></b></div>

The testo 635-1 temperature and humidity measuring instrument enables you to measure the temperature, air humidity and dew point – in compressed air as well. State-of-the-art technology and a large selection of probes, which are available as an option, enable this wide variety of measuring possibilities.

The testo 635-2 temperature and moisture meter allows you to carry out temperature and moisture measurements on a variety of different materials, surfaces and environments. This is made possible due to leading-edge technology and a wide selection of optionally available sensors.

The U-value is the most important value for proving the heat loss of a building. With the testo 635-2 thermohygrometer and compatible accessories from the U-value set, determining the U-value is now easier than ever.

The testo 645 humidity/temperature measuring instrument automatically indicates the measurement parameters of relative humidity, absolute humidity, dew point, degree of humidity, enthalpy and temperature at the touch of a button.

Ideal kit for IAQ professionals, with a focus on air flow measurement. You will receive the testo 400 universal IAQ measuring instrument with intuitive measurement menus, one vane probe head (Ø 16 mm), one vane probe head (Ø 100 mm) and one high-precision humidity/temperature probe head – all three can be attached to the Bluetooth<sup>&reg;</sup> handle supplied. For measurements at ceiling outlets, simply combine the 100 mm vane probe with the telescope (can be extended up to 1.0 m) and the 90° angle.

Ideal kit for IAQ professionals, with a focus on air flow measurement. You will receive the testo 400 universal IAQ measuring instrument with intuitive measurement menus, one hot wire probe head (including temperature and humidity sensor), one vane probe head (Ø 100 mm) and one high-precision humidity/temperature probe head – all three can be attached to the Bluetooth<sup>&reg;</sup> handle supplied. For measurements at ceiling outlets, simply combine the 100 mm vane probe with the telescope (can be extended up to 1.0 m) and the 90° angle.

The testo 6601 temperature and humidity probe is designed for monitoring critical indoor climates.

The testo 6602 temperature and humidity probe is designed for measurements in air conditioning ducts.

The testo 6603 temperature and humidity probe is designed for measurements in air conditioning ducts, is equipped with a high-precision, long-term stable humidity sensor from Testo and delivers precise measurement results.

The testo 6604 temperature and humidity probe is designed for measurements in processes that are difficult to access.

The testo 6605 temperature and humidity probe is equipped with a high-precision, long-term stable humidity sensor from Testo and delivers precise measurement results.

The testo 6611 temperature and humidity probe is designed for monitoring critical indoor climates.

The testo 6612 temperature and humidity probe is designed for measurements in air conditioning ducts.

The testo 6613 temperature and humidity probe is designed for measurements in processes that are difficult to access.

The testo 6617 temperature and humidity probe is designed for measurements in environments with aggressive media. With the built-in self-monitoring function, you can prevent faulty measurements or measurement interruptions – because it detects signs of corrosion at an early stage, thus the probe can be replaced in good time.

Control and calibrate Testo humidity probes easily: A defined humidity is generated in the two special containers with the aid of saline solutions (11.3 %RH and 75.3 %RH). The humidity probe is screwed into the first measuring chamber for testing and is thus exposed to the defined relative humidity. After an acclimatization time, a stable humidity is reached and the display value of the measuring instrument can be compared with it. The probe is then screwed into the second measuring chamber and the process is repeated.

With this practical kit, you can control and calibrate humidity probes quickly and easily.

Control and calibration kit for Testo humidity probes

Control and calibration kit for Testo humidity probes

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