Long lasting, continuous duty compressors offer less depth capabilities than the diaphragm or rocking piston compressors but produce considerably more air Medium pressure, oil free compressors are excellent for pond and lake aeration and de-icing Carbon vane self adjust to maintain maximum efficiency and are easily replaced when worn out all models have an 18 maximum operating depth, they come with air filter and 6 power cord Air outlet assemblies are available with two to six valves, allowing one pump to supply up to six air manifolds Please be sure to specify voltage desired on these compressors, all units shipped 115v unless otherwise specified 1 Year Warranty