120 volt, 208-240 volt
Content taken from Kasco website:
Teich-Aire™ Rocking Piston Compressors are designed and built to meet the demands of continuous-duty, year-round, large aeration applications. Available in 1/4, 1/2, or 3/4HP, these oil-less piston compressors can be used to replace or upgrade the compressor in our Robust-Aire™ Diffused Aeration Systems.
These compressors offer reliability and performance in applications such as ponds and lakes, water treatment systems, golf course ponds, fish farms, harsh industrial environments and many more.