Base unscrews for easy cleaning.
Large enough to acommodate standard size hydrometers or thermohydrometers. The 12" size works well for those making higher alcohol beers or for wine makers. The column screws-on the base to form a watertight sea and screws-off for easy cleaning and storage.
You must sanitize everything that comes in contact with your beer or cider, if you plan on pouring the sample back into the fermenter after testing.