This is D-518 Mini CO2 Bubble Counter for Aquarium. It is new and high quality never used. It is good choice for you!<!--Features --><p>FEATURES</p><ul class="p_f"><li>New and high quality</li><li>This CO2 bubble counter is accurate and the number is easy to read</li><li>It should be used with the diffuser and check valve</li><li>Fit for all kinds of aquarium</li><li>Material: Plastic</li></ul><!--Specifications --><!--Package Includes --><p>Package Includes</p><ul><li>1 x D-518 Mini CO2 Bubble Counter For Aquarium</li><li>1 x Rubber sucker</li></ul><!--Extra Info --><!--produts_compatibility -->