These premium quality Kimble Chase tubes feature sturdy, uniform bottoms and consistent lengths and have no marking spot. They are suitable for cell washing procedures. They are designed from ASTM Specification E890. The tubes are packed in convenient trays for ease of use on bench tops and in drawers; the trays are shrink-wrapped in plastic film, with tubes remaining in constant alignment for protection against in-transit breakage and contamination. These tubes are made from 51 expansion borosilicate glass. They meet requirements for the American Society for Testing and Materials (ASTM) E438, Type I, Class B, Standard Specification for Glass in Laboratory Apparatus, and the glass conforms to USP Type I requirements. Kimble Chase Life Science and Research Products manufactures scientific laboratory glassware under the Kimble Chase KIMAX brand. The company has its origins in Kimble Glass and Kontes Glass and is now a division of The Gerresheimer Group.