FujiFilm EB-530US Operation Manual page 61

(7) Remove the balloon ring (Big) slowly with your fingers
and attach it into the balloon installation groove of the
Ultrasonic Endoscope.
(8) Check that the balloon ring (Big) is attached into the
balloon installation groove.
(9) Feed water to the balloon from the balloon water feed
channel to discharge air from the balloon.
If air is not easily discharged from the balloon, press the
balloon with your fingers while feeding water to discharge
air completely.
(10) Attach the balloon ring (Small) into the balloon installation
groove at the distal end of the Ultrasonic Endoscope by
pushing back the ring with your fingers.
Chapter 5 Preparation for Use of Ultrasonic Endoscope
5-23