Aquarium bubbles air stone;suitable for : fish tank,aquariumMaterial : mineral, plastic;import diameter : 4.8mm/ 0.19 inchSize(approx) : 3.9 x 1.3cm / 1.5 inch x 0.49 inch(l x w);color : blueWeight : 176gProduct DescriptionCreates bubbles in fish tank while attached to an air pump.Used to increase the dissolved O2 level in the aquarium.It is an important instrument to successfully keep aquatic fish for respiration process.Package Contents : 40 x aquarium bubbles air stoneOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.