Engel 2nd Generation 2X2 Portable Air Pump for Engel and other live bait coolers and buckets.Includes 12vDC car adapter, flexible hose and weighted air stone. Alkaline Batteries (2 x size D) are not included. Top quality alkaline batteries last up 45 hours of continuous use. Air flow volume is 0.8L/Min (slow speed) and 1.0 L/Min (fast speed).