Product Name: Air Flow Control Valve; Material: Stainless Steel; Outlet Diameter: 4mm/0.16" Fit Air Tube Diameter: 4*6mm/0.16"x0.24"; Overall Size of Air Valve (Each): 30 x 21 x 8mm/1.2"x 0.84" x 0.32" (L*W*H) Manage the essential oxygen flow from your pond aerator or aquarium air pump with this convenient Air Control Valve. Designed for both aquarium and aquaculture uses, this air lever valve easily connects to aquarium tubing.