Brand new glass drop checker.
Suction cups included.
Solution is not included in this listing.
Size : 3cm diameter.
Simply add couple drops of test solution and water into the checker.
Stick the checker on the edge of the aquarium.
Ensure water level cover the opening of the checker.
Aquarium Carbon Dioxide CO2 Monitor PH Indicator Glass Drop Ball Checker Tester - B01B61I6WA