eWeLink organizes a giveaway every month. This month you can win one of the 10 Sonoff WiFi door sensors or one of the 10 one year free eWeLink Advanced subscriptions.
Please read the information on their Facebook post for more details on how to join their giveaway:
Product information
Sonoff DW2
WiFi door/window sensor. No need for a RF bridge. Directly communicates with your WiFi router / accesspoint.
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