Class B Graduated Burettes (TD), PTFE Screw Thread Stopcock & PTFE Key

Each burette features an advanced, grease-free screw thread stopcock housing a self-lubricating polytetrafluoroethylene (PTFE) key. Unlike traditional ground-glass keys that freeze easily or require hydrocarbon lubricants, this low-friction design keeps your titrants pure and provides fine-control, dropwise fluid delivery. To ensure sustained readability over years of laboratory service, the column is marked with permanently baked-in, high-contrast amber graduations that resist wearing down during aggressive washing or acid sanitization cycles.

Key Functional Benefits:

• Grease-Free Contamination Protection: The self-lubricated PTFE screw thread key eliminates stopcock grease completely, preventing hydrocarbon leaching from altering your chemical calculations
• Calibrated To Deliver (TD): Calibrated using automated fluid systems to ensure that the volume of liquid dispensed matches the graduation markings exactly, compensating for the thin fluid layer that naturally remains on the inner glass wall
• Permanent Amber Markings: Sharp, high-contrast amber graduations remain deeply fused to the glass matrix, preventing fading or wearing under harsh lab cleaning protocols
• Ergonomic Threaded Control: The screw thread mechanism provides highly predictable tactile feedback, allowing students and tech operators to isolate sharp titration endpoints with drop-by-drop precision