Polyethylene-stopper ST 45/40

Polyethylene stopper NS 45/40 is a precision-fit laboratory stopper intended for sealing standard ground-glass joints of size NS 45/40. Produced from low-density polyethylene (LDPE), the stopper conforms to DIN 12254 and features an octagonal head that provides a secure, non-slip grip during insertion and extraction. A distinctive blue lid completes the design, aiding quick identification among other laboratory consumables. This stopper from manufacturer Witeg is used to close round-bottom flasks, reaction vessels, adapters and similar glassware in organic synthesis, analytical chemistry and general laboratory practice. The polyethylene construction remains lightweight for single-use or repeated short-term applications. Each unit is supplied individually and has a net weight of 0,019 kg, making it easy to stock and handle. The standardised NS 45/40 taper guarantees interchangeability with glassware from different makers that follow the same joint specification. Whether employed in teaching laboratories, quality-control departments or research facilities, the stopper delivers a practical sealing solution that protects contents from contamination and evaporation during routine work.

This article is part of Ground-joint glass stoppers, in Stoppers, caps & closures.

Key features

• Pack size: 1 pc
• Joint size: NS 45/40
• Material: Low-density polyethylene (LDPE)
• Design: Octagonal
• Standard: DIN 12254
• Lid colour: Blue