Color: Green; Package Content: 2 x Air Stone; Material: Plastic,Mineral; Model: NAQ-101; Total Size: 320 x 18 x 10mm/ 12.5" x 0.7" x 0.4"(L*W*T) Evenly distributes fine bubbles through a super-porous, non-clogging wand. It is an important instrument to successfully keep aquatic fish for process. Add Oxygen to keep water roots healthy, put fishes live at ease. The air stone should be soaked in water for at least 15 minutes before use. When it is clogged with dirt or creating bubbles in a low rate, please wash it before reuse.