We stock a wide variety of the most commonly used flanged only heads in the industry. Tank heads are flat, not dished. All of our heads are made from carbon steel per the specifications in UL-58, section 7.2 and UL-142, section 5.2 Our heads have a 3/4” inside corner radius, and straight flange lengths range from 1-1/2" on the large diameter heads to 1/2" on the smaller ones. Outside circumferences are held to theoretical or to your specifications, with a tolerance of (+ - 1/8"). Heads have no center holes and no weld seams, and are stored inside to prevent oxidation. Every tank head is individually inspected, insuring all heads meet your specifications. If you do not find the size you need in our Stock Chart, call us for pricing on your special requirements. We will be happy to discuss a stocking program for any size that you use on a regular basis.