A resonance apparatus is used to locate the resonance positions in air columns. From these resonance positions, it is possible to calculate the speed of sound using the water level (measurements are included on the tube) and the frequency of the tuning fork used. This large, high quality resonance apparatus measures nearly 4' in height when fully assembled. The resonance tube comes with a heavy duty clamping support stand and jumbo 36" / 90cm graduated acrylic resonance tube. The resonance tube is over 1.5" / 40mm in diameter. The tube has permanent metric graduations along the full length of the tube (graduated in mm and cm).The acrylic resonance tube is connected by rubber tubing to a large aluminum water reservoir. The reservoir can be raised or lowered to adjust the length of the air column. Dual heavy duty universal clamps support the acrylic tube. Complete instruction manual is included. This resonance apparatus features materials and construction that are unsurpassed by any other manufacturer. The quality construction will yield many years of service.