I cant find specs either - so here is an sample while moving it from warm to cold places...
data...
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It seems to be dynamic. Typically, I see it send values most often 10s / 20s / 30s, sometimes 1 or more minutes.
But, you can poll the value using the right topic or the zigbe2mqtt "read" node.
I chose this one ↓ as it is pre-flashed (with coordinator firmware) and worked out of the box (and came with aerial)
https://www.ebay.co.uk/itm/224578308536
But there are many - here is a list of compatible devices.
PS, sorry for being slightly off-topic
