Kimax 25mL precision bore burette is permanently marked with an individual serial number. Supplied with a Certificate of Graduation Accuracy. Filling tube accepts ¼" I.D. flexible tubing. Filling is through the stopcock. Kim-Kap dust cap is included. Scale is durable white enamel. Designed from ASTM Specification E287, Class A requirements. Replacement stopcock is S6445. Kimble #: 17052F-25.