Product Description: A set of four popular low form glass beaker from Karter Scientific with Magnetic Stirring Bar. Contains 1 each 20, 50, 100 & 250ml glass low form beaker. Griffin Low Form Beakers are made of 3.3 borosilicate glass. Single Capacity Scale, Heavy-Duty, beaded rim and a spout designed to have excellent pouring characteristics., white marking spot, and uniform wall thickness throughout. 3.3 borosilicate is the highest level of inert glass available. Designed from ASTM Specification E960, Type I requirements. The Magnetic Stirring Bar with Pivot Ring included in this set has dimensions of 25x7mm. If you have any questions or concerns, please contact us. We are happy to make it right! Product Features: Beakers: 4 Sizes - 20, 50, 100, 250mlMagnetic Stir Bar: 25 x 7mm (1 inch) Octagonal, Pivot Ring, PTFEHigh quality inert 3.3 borosilicate glassASTM Specification E960, Type I requirementsSingle Metric Scale