Bait Bucket Aerator/Live Well Aerator Replacement Air Stones/Air Diffusers/Bubble Stones, twin pack, manufactured by Bubblemac Industries, Inc. Made in the U.S.A. This is not a cheap blue import stone that will "go away" in time. Bubblemac Air Diffusers Provide The Highest Oxygen Transfer Efficiency Of Any Aerator On The Market Today! {This IS NOT a Discard-A-Stone} 100% Glass Bonded Silica, Durable, Low Maintenance, 2 year guarantee The "Industry Standard" for fish farms and hatcheries worldwide. Creates a consistant medium fine bubble. Now available in a Bait Bucket Aerator Application. Self-Weighted, Non-Clogging, Standard Air Line Connection {5/32"}, Compatible With Most Models of Bait Bucket Aerator Pumps, Diffusers Measure 1/2" x 1/2" x 1 1/2" each. -- Each air diffuser will support approx. one pound of active minnows. Bubble Stones increase surface agitation, accelerate oxygen replenishment and help release carbon dioxide buildup. PROMOTES HEALTHIER / MORE LIVELY BAITFISH, "Ya'll Got Bubbles"? - SPECS: 100% Glass-Bonded Silica, Maximum Pore Size 140 Microns, Nominal Partical Retention 50 Microns, Flexural Strength 2500 PSI, Bubble Size 1-3 MM, UNLIMITED LIFETIME When Used in pH of 8.0 or Less!