EASYPRO AIR DIFFUSER MANIFOLDS DM6S 6 AIRSTONE DIFFUSERS. Many different sizes of inlet fittings available to meet your needs. Includes check valve to prevent water from filling air line when not in use.Polyethylene underlay keep diffusers from settling into the much and prevents sediment erosion during operation. Standard air diffusers (RAD650) are 6" long, standard airline connection is for 1/2" I. Includes: (4) 6 Airstone Diffuser. Recommended Airflow (CFM): 3.0 - 4.2. Size of Underlay: 24" x 24". The item "Air Diffuser Manifold 6 Diffusers for Pond Aeration- Alumina Airstones DM6S" is in sale since Monday, May 4, 2015. This item is in the category "Home & Garden\Yard, Garden & Outdoor Living\Ponds & Water Features\Outdoor Fountains". The seller is "graystone-creations" and is located in Cleveland, Georgia. This item can be shipped to United States.