The main difference between rimmed and rimless test tubes is the design of the opening. Rimmed test tubes feature a rolled lip that improves chip resistance and securely holds rubber bungs or push-fit caps, making them ideal for general laboratory work and education. Rimless test tubes have a smooth, fire-polished opening with a uniform diameter, allowing them to accept screw caps and perform better in microbiology, pathology and automated laboratory systems.
Although they appear almost identical, choosing the right type can improve safety, reduce contamination risks and ensure compatibility with laboratory equipment.
At Livingstone International, our range of glass test tubes includes both rimmed and rimless options in various sizes to suit educational, research, pathology and industrial laboratories. Pair them with our laboratory racks and trays for organised storage, safe handling and efficient laboratory workflows.
What Is a Rimmed Test Tube?
A rimmed test tube features a smooth, outward-rolled lip formed during manufacturing by heating and folding the glass at the opening. This reinforced edge provides additional strength where laboratory glassware is most susceptible to damage.
Why the Rim Matters
The rolled rim offers several practical advantages in everyday laboratory use.
The reinforced opening is more resistant to chipping, helping extend the life of the tube during repeated handling, washing and storage. This makes rimmed test tubes particularly suitable for teaching laboratories, chemistry classrooms and busy research environments where equipment is handled frequently.
The rolled edge also creates an excellent seating surface for rubber bungs and push-fit caps. These closures fit securely while remaining easy to remove, making rimmed tubes a popular choice for experiments requiring temporary sealing.
What Is a Rimless Test Tube?
A rimless test tube has a fire-polished opening without an outward lip, resulting in a consistent diameter from top to bottom. They are also commonly referred to as plain-end or culture tubes, depending on the manufacturer and intended application.
Where Rimless Tubes Excel
The uniform opening makes rimless test tubes ideal for use with precision screw caps, creating a more reliable airtight seal than rubber bungs. This helps minimise contamination and evaporation during sample storage or microbiological work.
For this reason, rimless test tubes are widely used in microbiology laboratories, pathology departments, pharmaceutical facilities and research environments where sample integrity is essential.
Their consistent diameter also allows them to fit accurately into automated laboratory racks, centrifuge adaptors and analytical instruments designed for precision handling.
Although the fire-polished edge is smooth and safe to handle, it does not provide the same level of chip resistance as a rolled rim, so slightly greater care is recommended during handling and cleaning.
Rimmed vs Rimless: A Direct Comparison
| Feature | Rimmed Test Tube | Rimless Test Tube |
|---|---|---|
| Open end finish | Rolled outward lip | Fire-polished flat edge |
| Chip resistance | Higher at rim | Lower at open edge |
| Closure compatibility | Rubber bungs, push-fit caps | Screw caps, precision-fit closures |
| Rack and adapter fit | Standard laboratory racks | Automated systems, centrifuge adaptors |
| Typical applications | School science, general chemistry, heating | Microbiology, clinical samples, culture work |
| Handling demands | Lower | Slightly higher at open end |
Which Test Tube Should You Choose?
The best option depends on your laboratory application.
Rimmed test tubes are commonly used in:
- School science laboratories
- Universities
- General chemistry laboratories
- Heating experiments
- Water bath applications
- Demonstration experiments
Their durable rolled rim helps withstand frequent handling while making it easier to insert and remove rubber bungs during practical experiments.
Rimless test tubes are preferred for:
- Microbiology laboratories
- Clinical pathology
- Biological sample storage
- Pharmaceutical laboratories
- Cell culture applications
- Automated laboratory systems
The combination of a uniform diameter and compatible screw caps provides a secure seal that helps protect samples from contamination while integrating seamlessly with modern laboratory equipment.
Does Glass Composition Matter?
Yes. The glass composition is often just as important as the rim design.
For applications involving heat, chemicals or sterilisation, borosilicate glass test tubes are the preferred choice. Borosilicate glass has a low coefficient of thermal expansion, making it highly resistant to thermal shock, chemical attack and repeated autoclaving.
Soda-lime glass is generally suitable for lower-temperature educational applications but is more susceptible to cracking when exposed to rapid temperature changes and should not be routinely autoclaved.
Frequently Asked Questions
1. Can rimless test tubes use rubber bungs?
Yes, but they generally do not provide as secure a fit as they do in rimmed test tubes. If your application requires rubber bungs, rimmed test tubes are usually the better option. Rimless tubes perform best with matching screw caps.
2. Are rimless test tubes stronger than rimmed ones?
Neither design is stronger overall. Rimmed test tubes offer greater protection against chipping around the opening because of their reinforced rolled lip. Overall durability depends more on the quality and composition of the glass, particularly whether it is manufactured from borosilicate glass.
3. What size test tube should I choose?
The appropriate size depends on your application and sample volume. Common laboratory sizes range from approximately 10 × 75 mm for small-volume testing through to 25 × 200 mm for larger reactions, sample preparation and culture work. When selecting laboratory glassware, always ensure the size, material and closure type are appropriate for your intended procedure.
Find the Right Laboratory Test Tubes
Whether you need durable rimmed test tubes for education and general laboratory work or rimless test tubes for microbiology and clinical applications, choosing the correct design helps improve efficiency, safety and sample integrity.
Explore Livingstone’s complete range of glass test tubes, along with compatible laboratory racks and trays, to build a laboratory setup that supports reliable, organised and accurate results.
References
- National Measurement Institute Australia 2023, Laboratory measurement standards and equipment specifications, Australian Government, viewed 13 July 2026.
- Safe Work Australia 2022, Managing risks of hazardous chemicals in the workplace, Safe Work Australia, Australian Government, viewed 13 July 2026.
