PTFE Needle Valve Burette Class AS Borosilicate 3.3 GLASSCO

Class AS borosilicate 3.3 burette fitted with a PTFE needle valve stopcock. Calibrated by delivery (TD, Ex) to ISO 385. The needle valve gives fine flow control—reliable to the last 0.05 ml.

Technical specifications

• Material: Borosilicate glass 3.3
• Class: AS (high accuracy)
• Calibration: By delivery, TD, Ex
• Stopcock: PTFE needle valve
• Standards: ISO 385, USP (United States Pharmacopeia)
• Metrological compliance: Eichordnung — DE-M (year) mark etched in glass
• Traceability: Batch number engraved directly into the glass

Applications

Acid-base, redox, and complexometric titrations. Suited to QC laboratories, pharmaceutical analysis, analytical chemistry, and advanced teaching labs. Class AS specified where minimum measurement uncertainty is required.

Traceability and certification

Batch number printed directly into the glass—cannot fade or peel. Batch certificate available on the manufacturer's website. Eichordnung conformity documented by the DE-M mark.

Why a PTFE needle valve

PTFE is inert to the vast majority of reagents. No grease required—eliminating contamination risk and the seized stopcocks common after titrations with concentrated bases. Dropwise control at the equivalence point is straightforward.