Rubber Stoppers / Rubber Bungs – Solid, Pack of 10 (21 mm Bottom)

These Solid Rubber Stoppers are durable, chemically resistant bungs designed for sealing a wide range of laboratory glassware. Each stopper features a bottom diameter of 21 mm, tapering to a top diameter of 24 mm, with a length of 28 mm. Supplied in packs of 10, they offer a reliable, leak‑resistant seal suitable for everyday school laboratory use.

Made from strong, flexible rubber, these stoppers withstand repeated handling and exposure to common laboratory chemicals, making them ideal for routine chemistry practicals and demonstrations.

Key Features

• Pack of 10 solid rubber stoppers
• Bottom diameter: 21 mm
• Top diameter: 24 mm
• Length: 28 mm
• Robust, flexible, and chemical‑resistant
• Provides a tight, secure seal for a variety of laboratory vessels
• Suitable for frequent classroom use

Ideal for School Science Lessons

Perfect for KS3–KS5 chemistry, these rubber bungs are ideal for:

• Sealing flasks, tubes, and reaction vessels
• Preventing gas escape during demonstrations
• Safely storing liquids and solutions
• Supporting heating, mixing, and containment experiments

Reliable and classroom‑ready, these stoppers are essential for any well‑equipped school science laboratory.