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
Iwata Air Valve 93591530
ANEST IWATA Air gauge for spray gun air regulator Air adjustment valve ES
ANEST IWATA Air gauge for spray gun air regulator pressure Air adjustment valve
ANEST IWATA Air gauge 2pcs for spray gun regulator pressure Air adjustment valve
