Labware includes a variety of products and equipment such as cylinders, lab glassware, and petri dishes for holding liquids and other substances in a laboratory environment. Additional labware items include ampules, beakers, carboys, and various lab bottles and test tubes. When choosing the right piece of labware for a given application, there are some important factors to consider, including material type, durability, and capacity. Labware comes in a variety of material types, such as glass, and plastic. Glass is an inert brittle solid, and is heat and corrosion resistant. Pyrex labware, for example, is selected for its strength and chemical-resistant properties. Borosilicate, a common type of glass used in labware materials, is sometimes manufactured to conform to government specifications. Plastics, such as polypropylene (PP) and polyvinyl chloride (PVC), are typically lighter than glass, and have varying levels of transparency, rigidity and flexibility. Labware comes in a wide array of capacities. A separatory funnel, used to distinguish liquid densities, commonly comes in many different capacities such as 50, 500, and 1000mL. Labware also comes in many shapes. Volumetric flasks, used for mixing, sampling and filling, have many different shapes, heights, and mouth widths, and sometimes have a flat bottom, or come with a stopper or other cap type. A pipet is labware that is used to draw, measure, and transfer liquids. A pipet typically has metric (mL) graduations, and comes in various millimeter (mm) lengths Serological, volumetric (also known as transfer), or measuring (also known as Mohr) are common pipet types. Blow-out pipets are often used in lab applications. Labware is commonly used by researchers, chemists, and biologists in the industrial, chemical, education, research and life sciences industries.