I check the received model

There is a whole lot of reference, the model I received is well stamped 19DZT

Where to buy this equipment?

On the date of writing of this Retex:

• not yet found on Amazon
• on Ali Express, I do not advise any seller because this multitude of references freaks out

I integrate this box with Zigbee2MQTT

I switch Zigbee2MQTT to pairing mode. 

I add two batteries (not included)

The pairing starts…

The Open/Closed contract is well-functioning. Clearly the information on the batteries does not go up (yet?)

I'm going to Home Assistant.

I can find my equipment there

It is perfectly integrated!