Locate the right elements

3
5
4
6
2
1
  • 1 O₂ switch (between Aux.O₂ and Add.O₂)
  • 2 APL Valve
  • 3 On/Off key
  • 4 Control rotary knob
  • 5 O₂+ button (O₂ flush)
  • 6 External fresh-gas outlet
well done