A bubble counter is an important accessory in a CO2 system. Choosing a premium accessory is vitally important. INSTRUCTION: 1. Unscrew the top cap and fill 3/4 with water, firmly screw the top back on. 2. Unscrew the compression collar from the bottom of the bubble counter, feed tubing through the collar, and firmly tighten to hold the tubing in place. 3. Unscrew the compression collar from the top of the bubble counter, feed tubing through the collar, and firmly tighten to hold the tubing in place. 4. Use suction cups to hold the bubble counter in place. PACKAGE INCLUDED: 1 x Bubble Counter