Motorola RMU2040 Quick Reference page 97

RM SERIES
DISPLAY RADIO FEATURES
Antenna
Channel Selector
On/Off Volume Knob
LED Indicator
Microphone
Rugged Speaker Grill
Menu button
Use to lock keypad
Front Buttons
Use < and > to scroll
up/down menu settings
Applies to RMU2080d
Accessory
Connector
Lithium Ion
Battery
PTT (Push-to-Talk)
Button
SB1 – Monitor Button
SB2 – Channel Select