Penn Plax AT2K3 Aquarium Air Pump, 110-Volt, Large DESIGNED FOR QUIET OPERATION: with rubber armature, silicone polymer flappers, a thick cover, and raised rubber feet, this air pump is of the quietest on the market SINGLE AIR OUTLET: this air pump accepts standard 3/16 airline tubing, and is ideal for tanks up to 30 gallons large RELIABLE AND DURABLE: Penn Plax has designed this pump with reliability and durability in mind  this pump will last you years  at an affordable price and quiet operation COMPATIBLE WITH ALL AQUARIUMS: safe for freshwater, marine, and reef aquariums. Whatever your aeration needs; the Air Tech pump has you covered This air pump has a powerful motor with a quiet design casing Air-tech 2k1 is blue in color and has a very unique diaphram Air pump features include non-skid feet, a rubber mount armature and silicon polymer flappers