DescriptionThese test tubes were produced with the intention of easy manipulation within a laboratory setting. The spiral affords simple opening and closing. They can be used for mixing heating or holding small quantities of chemicals for assays, as well as tissue culture, blood banks and other laboratory experiments.Features- Color: Transparent and black. - Material: Glass. - Size: 10.20X1.20X1.20cm/4.01X0.47X0.47 inch. - Capacity: 5ml. - Glass test tubes, round bottom with screw cap, they are easy to fill and the lids fit tightly, no leaks. - Smooth wall products, good transparency, accurate measurement scale. - It will withstand temperature change up to and including boiling of samples, as well highly chemically resistant.- Widely used in laboratory, research facility, food coloring, craft, etc. - The use of high-quality glass materials, smooth inner wall, can effectively reduce liquid adsorption.