Our standard thistle tubes have a stem that is 7mm in diameter. They are made from borosilicate glass and are available in different lengths.
WARNING: This product can expose you to chemicals including arsenic, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
Our products are not toys. Use in a laboratory or educational setting only. Not for children 13 and under.