This 20 gallon rectangular tank with sump is 18" long, 14" wide and 12" high. This tank has a .175" nominal wall thickness. Tank comes standard with a 3/4" FNPT polypropylene with Santoprene gasket and a 5" vented lid. Tank weighs 12 lbs. Tanks are manufactured from medium-density polyethylene with U.V. inhibitors and designed for containment of liquids of up to 1.7 specific gravity. Tank walls are translucent for level viewing and equipped with gallon indicators.