Uniden UM255 Owner's Manual page 21

Specifications
General
Antenna Impedance
Microphone
Speaker
Operating Temperature
Range
Transmitter
Power Output
Frequency Range
Receiver
Frequency Range
50 Ω nominal
2 kΩ condenser mic element with coiled cord
45mm, 8 Ω, 2W
0 °C to + 50 °C
4 watt
26.965 to 27.980 MHz
26.965 to 27.980 MHz
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