Ideal storage tank for replacement or customized applications. Chosen by both Alternate Energy Technologies and Heliodyne for use in their solar hot water systems. 2” Non-CFC Foam Insulation - Foam insulation traps heat within the glass-lined tank, saving energy. Tank R-Value of 16.7 Anode Rod - Promotes longer tank life through protection against corrosion of tank interior. (Price subject to change without notice. Check stock before order)