Manufactured from 51 expansion borosilicate glass conforming to USP Type I and ASTM E438, Type I, Class B requirements.

• Permanent ceramic labels are located ³/₄" from the open end
• All tubes have sturdy, uniform bottoms and consistent lengths
• Borosilicate glass tubes have excellent chemical resistance against sodium leaching

These Chase brand Mark-M™ glass culture tubes feature a permanent vertical ceramic label, fused to the glass, which is easily written on with marker or pencil.