Self-zeroing burette mounts on a glass bottle. Includes a PTFE needle valve stopcock, intermediate stopcock and rubber bellows. Class A, ASTM E-287, meets USP standards, individually serialized and certified. Includes Schellbach backing for easy reading of liquid levels. With amber graduations. Manufactured from precision bore tubing and calibrated To Deliver (TD, Ex) on computer-controlled machines. Glass bottles with ground glass joints are sold separately. 500ml bottle size is compatible with the 10ml automatic burette. 2000ml bottle size is compatible with the 25ml and 50ml automatic burettes.