Lutron Electronics GCH-2018 Operation Manual page 8

3-1 Display
3-2 Power Button
3-3 Hold Button ( Esc Button )
3-4 REC Button ( Enter Button )
3-5 Set Button ( Button )
▲
3-6 Alarm/Dew point Button ( Button )
▼
3-7 Battery Compartment/Cover
3-8 Stand
3-9 Input socket
3-10 RS-232 Output Terminal
3-11 DC 9V Power Adapter Input Socket
3-12 Reset button
3-13 CO2 Probe Head
3-14 CO2 Probe Handle
3-15 CO2 Probe Plug
3-16 Humidity Probe Head
3-17 Humidity Probe Handle
3-18 Humidity Probe Plug
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