10x Air Stone Bubble Curtain Bar Aquarium Aerator Pump Hydroponics 4" This is an ideal accessory for added aeration, circulation and decorative highlights. It creates a dazzling underwater scene while also increasing surface agitation. All you have to do is attach the airline tubing to the air stone inlet and place it in desired location. Dimensions: 4.0" L x 1.0" W x 0.75" H Color: Blue Package include: 10 pieces of 4 air stone bar