Iwata Kustom TR airbrush. This part fits the following models.
Cutaway Preset Handle for HP-AP/BP/SBP Iwata Airbrushes
Cutaway Preset Handle for CM-C2-Plus Iwata Custom Micron IWS-5855
IWS-5851 Preset Handle for Custom Micron CM-B/SB/C Iwata Airbrush
Preset Handle for Iwata Eclipse, Revolution & HP-C/BC Airbrush IWA-1552
Preset Handle for CM-B2/C2/SB2 Iwata Airbush
Preset Handle for HP-A/B/SB [IWA-1551]