35 INCH || Long barometer tube with bulb on shorter limb measures 35 inches TO MEASURE AIR PRESSURE || Used to measure air pressure in any environment HOW TO || Liquid will move up the barometer tube as air pressure increases DURABLE & STURDY || Made of high quality Borosilicate 3.3 glass - Built to last GREAT FOR EXPERIMENTS || An essential tool for showing how the weather impacts air quality - Designed for use in the laboratory but great for education in the home Long barometer tube with bulb on shorter limb measures 35 inches. Used to measure air pressure in any environment. Liquid will move up the barometer tube as air pressure increases. Made of high quality Borosilicate 3.3 glass. Built to last. An essential tool for showing how the weather impacts air quality. Designed for use in the laboratory but great for education in the home. Eisco Labs proudly manufactures its own products using state-of-the-art equipment, and following the highest standards of quality control. Each product is carefully designed by a team of laboratory professionals and experienced engineers with quality and durability in mind. They are manufactured with only the highest grade, raw materials and according to international quality standards to ensure that they can withstand use in even the toughest laboratory environments.