Waters GCT Premier Operator's Manual page 27

DCI inner source assembly:
Handle
Thumbscrews
The FI/FD inner source consists of a removable probe holding the FI/FD
emitter. The emitter consists of a tungsten wire on which there are carbon
microneedles.
FI/FD inner source assembly:
Rotational
Micrometer
adjustment knob
Probe guide rod
Source type identifier
Probe stop
Isolation valve
Vent valve
Shaft
DCI source
Emitter
Ion source 1-5