The device is 50mm x 35mm x 16mm (LxWxH) and its weight is 21 grams.
(2 x 1.4 x 0.6 inches and 0.7 ounces)

The Corona-Tracer is a proximity sensor which will detect if a person is engaging with another person within about 2 meter, 6 feet in the US.
If so, a unique code is exchanged between the two devices which accounts for one event.
If the two (or more) persons stay in this position for a longer period of time, every 10 seconds a new event will be generated and stored in the devices.

No there is no display or other indicator on the device.

No, the Corona-Tracer is not waterproof and must be worn under a jacket or other coverage when the worker has activities outside and in the rain.

The system is targeted towards business use in factories, warehouses, distribution centers, hospitals, offices and the like.
The device is not meant to be used by consumers in the public space.

The Corona-Tracer is programmed so that the Bluetooth signal only travels around 2 meter, 6 feet in the US.
It sends its ID and then listens to the surroundings also in this 2-meter range.
When a co-worker with a Corona-Tracer is within range, they exchange the unique IDs and these are stored in memory.
For more information about the distance, read here: https://www.corona-tracer.com/explanation

The Corona-Trace uses Bluetooth wireless technology which is 2.4Ghz.
This is the same frequency as WiFi.
Radio waves are electro-magnetic waves, just like light, but much less intense.
These wireless signals are everywhere and there is no scientific data that it can cause cancer.

The Corona-Tracer does not make any sound when in contact within 2 meters, 6 feet in the US of another Corona-Tracer.

No, there is no temperature increase.