Single Solar Vacuum Tube

Excellent for solar water heating systems and DIY projects. Boil water using only sunlight! 1 tube can raise 1 liter of water from 60'F (15'C) to 212'F (100'C) in one hour of direct sunlight. Use this box tube for your own science or hobby projects, or for building your own powerful solar-powered home heating systems.  Includes: 20 1/2" long (about 500mm) 2 1/4" outside diameter (about 58mm) 1 3/4" inside diameter (about 43mm) Double wall structure with vacuum between walls Super-absorbent inner tube coating quickly soaks up solar energy Steel, aluminum, and copper coatings for infrared reflective insulation Incredible thermos-like properties can keep water hot even over night Finally you have a reliable U.S. source for high-grade solar vacuum tubes, also known as solar evacuated tubes. Unlike many solar vacuum tube suppliers we offer a standard 100% shipping protection guarantee. Make sure other vacuum tube suppliers you are considering offer this type of no-questions guarantee for