COLIBYOU Refrigerator Thermometer Wireless Digital Freezer Thermometer with 2PCS Wireless Sensors with Audible Alarm for Indoor Outdoor Thermometer (Battery not Included)

Digital alarm thermometer equipped with sensors,
the wireless sensor have 328ft remote range,with strong signal penetration
thermometer monitor (enhanced 433 MHz), can provide the accurate measurements
for freezer,indoor or outdoor temperature.Wireless freezer thermometer with
Min/Max Display in °F or °C.

Feature:
Transmission range up to 328ft
Transmission frequency: 433 Mhz,Update Rate: 60 seconds
Indoor Temperature range: 0℃~50℃（32℉ ~ 122℉）
Outdoor Temperature range: -40℃~60℃（-40℉ ~ 140℉）
Remote temperature range: lithium batteries: -40°F to 140°F
Non-lithium batteries: -4°F ~ 140°F

Specifications: 
Weight: 210G 
Power Supply: 1 Main Unit 2*AAA(not included), 2 Transmitters 4*AA (not included)
Package Includes: 1 Main Unit + 2 Transmitters (batteries not included) 

Note:
don't put the transmitter directly in the rain
Don't install the reverse battery,don't put the receiver near metal
Pls kindly use high-quality batteries for main unit and transmitters,it's more better
 About the alarm function, the alarm will ring only 10minutes later not immediately when the
temperature reach the max/min set temperature.