... wireless model, 433M wireless model, 780M wireless model, 799M wireless model, 868M wireless model, 915M wireless model, 433MHz wireless model, 780MHz wireless model, 779MHz wireless model, 868MHz wireless model, 915MHz wireless ... for users to connect plate bottom. Spiral antenna confirms communicate effect at the same time to ... 22 x 22 x 5 (mm) without antenna Working environment-20°C ~ 40°C;Humidity ...