Behlen Mfg 224 Poly Round End Tank (approx. 100 gal.)Poly Round End Tanks are made with a durable, seamless design that helps resists breakage. All round end tanks have an extra heavy duty, molded rim and an extra deep sidewall rib design for additional strength. A Heavy Duty, molded in aluminum drain fitting and 1 1 4poly drain plug ensure a long life. All Poly tanks made with poly , tested to 20F, corrosion free, impact resistant and recyclable.