Vessel has Duran style O-Ring Flange. Flanges Can Either be Sealed with an O-Ring or Grease. Circulator Jacket has Internal Theads for Detachable Hose Barbs. Supplied with Nylon Bushings and Polypropylene Barbs. Drain Valve Stem Seats Flush to Inside Radius of Vessel Bottom. Drain Drip Stem is a Nominal O.D. for Us with a Standard Compression Fitting. Four Equaly Spaced Baffle Indents Improve Stirring Activity.