A popular student-use device for determining the wavelength and velocity of sound by resonating an air column with a tuning fork of a known frequency. The transparent plastic tube is connected to a water reservoir can by flexible tubing. Raising or lowering the water can adjusts the air column at the top of the tube.
GS-910B has a 120 cm tube with a permanently mounted 110 cm scale. A clamp for holding a tuning fork is included.
Tuning fork is not included.