Specification: Material: Mineral stone + plastic Quantity: 2pcs Color: Grey Feature: Help to keep fish healthy and adds extra beauty to the aquarium It is an important instrument to keep fish respiration. The air stone fits for diameter 0.15''/4mm soft tube. The air stone making bubbles in fish tank while attaching to an air pump(air pump is not included). Package includes: 2 x Aquarium bubble stones
