This is the air valve shaft found behind the trigger on ls400 and lph400spray guns. It is part 14 in ls400 repair diagrams and part 11 in the lph400 diagrams.
Anest Iwata Air valve seat assy 93843530 WS-400 LS-400 W-400 LPH-400 and more
Anest Iwata Air valve seat assy 93001640 KIWAMI4 WIDER4 KIWAMI-1 WIDER1 WIDER2
Anest Iwata Air valve seat assy 93001790 KIWAMI4 WIDER4 KIWAMI-1 WIDER1 WIDER2
Iwata Air Valve 93591530
Iwata Air Valve Spring LS400 WS400 LPH400 93719530
ANEST IWATA Air gauge for spray gun air regulator Air adjustment valve ES