These durable rubber stoppers with a single hole are ideal for securely sealing laboratory glassware during science experiments in primary, secondary and college settings. Designed for safe use with chemicals, they help teachers and students carry out investigations with confidence.

• Made from high-quality rubber, resistant to acids, alkalis and ammonia

• Bottom diameter: 21mm; Top diameter: 24mm; Length: 28mm

• Single 5mm hole for tubing or apparatus

• Temperature stable from -20°C to 70°C

• Pack of 10 for classroom convenience

• Easy to clean and suitable for repeated use

• Please note: Extreme care must be used when inserting glass into the holes in rubber stoppers.  See CLEAPSS for details.