Do you want to have a convenient and practical test tube with side arm? If you want, then you can consider our product. Made by premium and sturdy material, not easy to damage and break. A sealed side arm test tube is equivalent to an ordinary test tube with a single hole plug. Features - ColorTransparent - Material: Glass. - Size: 18.00X4.50X1.80cm/7.07X1.77X0.71in. - A side arm test tube is a kind of laboratory glassware, which is a branch tube installed on the basis of an ordinary test tube. - A sealed side arm test tube is equivalent to an ordinary test tube with a single hole plug. - The gas commonly used in the laboratory with the liquid through multiple test tubes at the same time, and the chemical changes between the liquid and the Can be clearly seen to determine the chemical properties of the gas. - When heating, keep the outer wall of the test tube free of water droplets to prevent uneven heating and bursting. - A test tube is equivalent to a Kipp's apparatus that is easy to assemble. Package list: 6 Tubes with Side Arm