Natural Rubber Stoppers
Manufacturer: United Scientific
The Natural Rubber Stoppers from United Scientific are a laboratory staple, engineered to provide an airtight and secure seal for flasks, test tubes, and carboys. Crafted from premium black natural rubber, these stoppers are designed for long-term pliability, ensuring they don't become brittle or lose their grip even after repeated use. Each stopper is clearly marked with its size in raised figures for quick identification. These are ideal for use with non-aggressive or concentrated solutions and feature a low sulfur content. Available in solid, one-hole, and two-hole versions, they provide the versatility needed for everything from simple storage to complex distillation setups.
Description
In Stock!
Lead Times May Vary
Features:
- The natural rubber formula resists hardening, allowing the stopper to conform perfectly to the interior contours of glass necks for a leak-proof seal
- Hole Configurations:
- Solid: Best for sample storage and transport
- 1-Hole / 2-Hole: Essential for inserting glass tubing, thermometers, or funnels for gas collection and vacuum applications
- Can be safely sterilized (autoclavable) for biological or sterile chemistry applications
- Best suited for aqueous solutions, dilute acids, and bases. (Note: Not recommended for use with petroleum-based solvents or strong oxidizers)
Sizing & Maintenance Tips:
- Proper Sizing: To ensure a secure fit, choose a stopper where the "Top Diameter" is larger than the opening of your glassware, and the "Bottom Diameter" is smaller. A properly sized stopper should sit approximately halfway into the neck.
- Lubrication: When inserting glass tubing into 1-hole or 2-hole stoppers, use a small amount of glycerin or soapy water as a lubricant to prevent the glass from snapping and causing injury.
- Storage: Store stoppers in a cool, dry place away from direct sunlight (UV) to prevent "cracking" or surface oxidation over several years.
| SKU | Bottom Outer Diameter | Hole Diameter | Size | Temperature Range | Top Outer Diameter | Type | Height |
|---|---|---|---|---|---|---|---|
| RST00-H2 | 10 mm | 3 mm | 00 | -25°C to 70°C (-13°F to 158°F) | 15 mm | Double Hole | 25 mm |
| RST12-H | 54 mm | 5 mm | 12 | -25°C to 70°C (-13°F to 158°F) | 64 mm | Single Hole | 25 mm |
| RST12-H2 | 54 mm | 5 mm | 12 | -25°C to 70°C (-13°F to 158°F) | 64 mm | Double Hole | 25 mm |
| RST12-S | 54 mm | 5 mm | 12 | -25°C to 70°C (-13°F to 158°F) | 64 mm | Solid | 25 mm |
| RST14-H | 75 mm | 5 mm | 14 | -25°C to 70°C (-13°F to 158°F) | 90 mm | Single Hole | 25 mm |
| RST14-H2 | 75 mm | 5 mm | 14 | -25°C to 70°C (-13°F to 158°F) | 90 mm | Double Hole | 25 mm |
| RST14-S | 75 mm | 5 mm | 14 | -25°C to 70°C (-13°F to 158°F) | 90 mm | Solid | 25 mm |
| RST15-H | 83 mm | 5 mm | 15 | -25°C to 70°C (-13°F to 158°F) | 103 mm | Single Hole | 25 mm |
| RST15-H2 | 83 mm | 5 mm | 15 | -25°C to 70°C (-13°F to 158°F) | 103 mm | Double Hole | 25 mm |
| RST15-S | 83 mm | 5 mm | 15 | -25°C to 70°C (-13°F to 158°F) | 103 mm | Solid | 25 mm |
| RST16-H | 90 mm | 5 mm | 16 | -25°C to 70°C (-13°F to 158°F) | 127 mm | Single Hole | 25 mm |
| RST16-H2 | 90 mm | 5 mm | 16 | -25°C to 70°C (-13°F to 158°F) | 127 mm | Double Hole | 25 mm |
| RST16-S | 90 mm | 5 mm | 16 | -25°C to 70°C (-13°F to 158°F) | 127 mm | Solid | 25 mm |
| RST5A-H | 24 mm | 5 mm | 5 1/2 | -25°C to 70°C (-13°F to 158°F) | 28 mm | Single Hole | 25 mm |
| RST5A-H2 | 24 mm | 5 mm | 5 1/2 | -25°C to 70°C (-13°F to 158°F) | 28 mm | Double Hole | 25 mm |
| RST5A-S | 24 mm | 5 mm | 5 1/2 | -25°C to 70°C (-13°F to 158°F) | 28 mm | Solid | 25 mm |
| RST7A-H | 31 mm | 5 mm | 7 1/2 | -25°C to 70°C (-13°F to 158°F) | 39 mm | Single Hole | 25 mm |
| RST7A-H2 | 31 mm | 5 mm | 7 1/2 | -25°C to 70°C (-13°F to 158°F) | 39 mm | Double Hole | 25 mm |
| RST7A-S | 31 mm | 5 mm | 7 1/2 | -25°C to 70°C (-13°F to 158°F) | 39 mm | Solid | 25 mm |
| RST8A-H | 36 mm | 5 mm | 8 1/2 | -25°C to 70°C (-13°F to 158°F) | 43 mm | Single Hole | 25 mm |
| RST8A-H2 | 36 mm | 5 mm | 8 1/2 | -25°C to 70°C (-13°F to 158°F) | 43 mm | Double Hole | 25 mm |
| RST000-H | 8 mm | 3 mm | 000 | -25°C to 70°C (-13°F to 158°F) | 13 mm | Single Hole | 25 mm |
| RST000-S | 8 mm | 3 mm | 000 | -25°C to 70°C (-13°F to 158°F) | 13 mm | Solid | 25 mm |
| RST8A-S | 36 mm | 5 mm | 8 1/2 | -25°C to 70°C (-13°F to 158°F) | 43 mm | Solid | 25 mm |
| RST00-H | 8 mm | 3 mm | 00 | -25°C to 70°C (-13°F to 158°F) | 13 mm | Single Hole | 25 mm |
| RST9A-H | 38 mm | 5 mm | 9 1/2 | -25°C to 70°C (-13°F to 158°F) | 46 mm | Single Hole | 25 mm |
| RST9A-H2 | 38 mm | 5 mm | 9 1/2 | -25°C to 70°C (-13°F to 158°F) | 46 mm | Double Hole | 25 mm |
| RST00-S | 10 mm | 3 mm | 00 | -25°C to 70°C (-13°F to 158°F) | 15 mm | Solid | 25 mm |
| RST9A-S | 38 mm | 5 mm | 9 1/2 | -25°C to 70°C (-13°F to 158°F) | 46 mm | Solid | 25 mm |
| RST0-H | 13 mm | 3 mm | 0 | -25°C to 70°C (-13°F to 158°F) | 17 mm | Single Hole | 25 mm |
| RST0-H2 | 13 mm | 3 mm | 0 | -25°C to 70°C (-13°F to 158°F) | 17 mm | Double Hole | 25 mm |
| RST0-S | 13 mm | 3 mm | 0 | -25°C to 70°C (-13°F to 158°F) | 17 mm | Solid | 25 mm |
| RST10A-H | 45 mm | 5 mm | 10 1/2 | -25°C to 70°C (-13°F to 158°F) | 53 mm | Single Hole | 25 mm |
| RST10A-H2 | 45 mm | 5 mm | 10 1/2 | -25°C to 70°C (-13°F to 158°F) | 53 mm | Double Hole | 25 mm |
| RST10A-S | 45 mm | 5 mm | 10 1/2 | -25°C to 70°C (-13°F to 158°F) | 53 mm | Solid | 25 mm |
| RST10-H | 42 mm | 5 mm | 10 | -25°C to 70°C (-13°F to 158°F) | 50 mm | Single Hole | 25 mm |
| RST10-H2 | 42 mm | 5 mm | 10 | -25°C to 70°C (-13°F to 158°F) | 50 mm | Double Hole | 25 mm |
| RST10-S | 42 mm | 5 mm | 10 | -25°C to 70°C (-13°F to 158°F) | 50 mm | Solid | 25 mm |
| RST11A-H | 50 mm | 5 mm | 11 1/2 | -25°C to 70°C (-13°F to 158°F) | 63 mm | Single Hole | 25 mm |
| RST11A-H2 | 50 mm | 5 mm | 11 1/2 | -25°C to 70°C (-13°F to 158°F) | 63 mm | Double Hole | 25 mm |
| RST11A-S | 50 mm | 5 mm | 11 1/2 | -25°C to 70°C (-13°F to 158°F) | 63 mm | Solid | 25 mm |
| RST11-H | 5 mm | 5 mm | 11 | -25°C to 70°C (-13°F to 158°F) | 48 mm | Single Hole | 25 mm |
| RST11-H2 | 5 mm | 5 mm | 11 | -25°C to 70°C (-13°F to 158°F) | 48 mm | Double Hole | 25 mm |
| RST11-S | 5 mm | 5 mm | 11 | -25°C to 70°C (-13°F to 158°F) | 48 mm | Solid | 25 mm |
| RST13-H | 58 mm | 5 mm | 13 | -25°C to 70°C (-13°F to 158°F) | 68 mm | Single Hole | 25 mm |
| RST13-H2 | 58 mm | 5 mm | 13 | -25°C to 70°C (-13°F to 158°F) | 68 mm | Double Hole | 25 mm |
| RST13-S | 58 mm | 5 mm | 13 | -25°C to 70°C (-13°F to 158°F) | 68 mm | Solid | 25 mm |
| RST1-H | 14 mm | 4 mm | 1 | -25°C to 70°C (-13°F to 158°F) | 19 mm | Single Hole | 25 mm |
| RST1-H2 | 14 mm | 4 mm | 1 | -25°C to 70°C (-13°F to 158°F) | 19 mm | Double Hole | 25 mm |
| RST1-S | 14 mm | 4 mm | 1 | -25°C to 70°C (-13°F to 158°F) | 19 mm | Solid | 25 mm |
| RST2-H | 16 mm | 5 mm | 2 | -25°C to 70°C (-13°F to 158°F) | 20 mm | Single Hole | 25 mm |
| RST2-H2 | 16 mm | 5 mm | 2 | -25°C to 70°C (-13°F to 158°F) | 20 mm | Double Hole | 25 mm |
| RST2-S | 16 mm | 5 mm | 2 | -25°C to 70°C (-13°F to 158°F) | 20 mm | Solid | 25 mm |
| RST3-H | 18 mm | 5 mm | 3 | -25°C to 70°C (-13°F to 158°F) | 24 mm | Single Hole | 25 mm |
| RST3-H2 | 18 mm | 5 mm | 3 | -25°C to 70°C (-13°F to 158°F) | 24 mm | Double Hole | 25 mm |
| RST3-S | 18 mm | 5 mm | 3 | -25°C to 70°C (-13°F to 158°F) | 24 mm | Solid | 25 mm |
| RST4-H | 20 mm | 5 mm | 4 | -25°C to 70°C (-13°F to 158°F) | 26 mm | Single Hole | 25 mm |
| RST4-H2 | 20 mm | 5 mm | 4 | -25°C to 70°C (-13°F to 158°F) | 26 mm | Double Hole | 25 mm |
| RST4-S | 20 mm | 5 mm | 4 | -25°C to 70°C (-13°F to 158°F) | 26 mm | Solid | 25 mm |
| RST5-H | 23 mm | 5 mm | 5 | -25°C to 70°C (-13°F to 158°F) | 27 mm | Single Hole | 25 mm |
| RST5-H2 | 23 mm | 5 mm | 5 | -25°C to 70°C (-13°F to 158°F) | 27 mm | Double Hole | 25 mm |
| RST5-S | 23 mm | 5 mm | 5 | -25°C to 70°C (-13°F to 158°F) | 27 mm | Solid | 25 mm |
| RST6A-H | 27 mm | 5 mm | 6 1/2 | -25°C to 70°C (-13°F to 158°F) | 34 mm | Single Hole | 25 mm |
| RST6A-H2 | 27 mm | 5 mm | 6 1/2 | -25°C to 70°C (-13°F to 158°F) | 34 mm | Double Hole | 25 mm |
| RST6A-S | 27 mm | 5 mm | 6 1/2 | -25°C to 70°C (-13°F to 158°F) | 34 mm | Solid | 25 mm |
| RST6-H | 26 mm | 5 mm | 6 | -25°C to 70°C (-13°F to 158°F) | 32 mm | Single Hole | 25 mm |
| RST6-H2 | 26 mm | 5 mm | 6 | -25°C to 70°C (-13°F to 158°F) | 32 mm | Double Hole | 25 mm |
| RST6-S | 26 mm | 5 mm | 6 | -25°C to 70°C (-13°F to 158°F) | 32 mm | Solid | 25 mm |
| RST7-H | 30 mm | 5 mm | 7 | -25°C to 70°C (-13°F to 158°F) | 37 mm | Single Hole | 25 mm |
| RST7-H2 | 30 mm | 5 mm | 7 | -25°C to 70°C (-13°F to 158°F) | 37 mm | Double Hole | 25 mm |
| RST7-S | 30 mm | 5 mm | 7 | -25°C to 70°C (-13°F to 158°F) | 37 mm | Solid | 25 mm |
| RST8-H | 33 mm | 5 mm | 8 | -25°C to 70°C (-13°F to 158°F) | 41 mm | Single Hole | 25 mm |
| RST8-H2 | 33 mm | 5 mm | 8 | -25°C to 70°C (-13°F to 158°F) | 41 mm | Double Hole | 25 mm |
| RST8-S | 33 mm | 5 mm | 8 | -25°C to 70°C (-13°F to 158°F) | 41 mm | Solid | 25 mm |
| RST9-H | 37 mm | 5 mm | 9 | -25°C to 70°C (-13°F to 158°F) | 45 mm | Single Hole | 25 mm |
| RST9-H2 | 37 mm | 5 mm | 9 | -25°C to 70°C (-13°F to 158°F) | 45 mm | Double Hole | 25 mm |
| RST9-S | 37 mm | 5 mm | 9 | -25°C to 70°C (-13°F to 158°F) | 45 mm | Solid | 25 mm |
| RST13A-S | 58 mm | 5 mm | 13 1/2 | -25°C to 70°C (-13°F to 158°F) | 68 mm | Solid | 25 mm |
| SKU | Color | Autoclavable | Includes | Material | Durometer |
|---|---|---|---|---|---|
| RST00-H2 | Black | Yes | Approx. 90 Stoppers | Natural Rubber | 60 ±5 |
| RST12-H | Black | Yes | Approx. 5 Stoppers | Natural Rubber | 60 ±5 |
| RST12-H2 | Black | Yes | Approx. 5 Stoppers | Natural Rubber | 60 ±5 |
| RST12-S | Black | Yes | Approx. 5 Stoppers | Natural Rubber | 60 ±5 |
| RST14-H | Black | Yes | Approx. 1 Stopper | Natural Rubber | 60 ±5 |
| RST14-H2 | Black | Yes | Approx. 1 Stopper | Natural Rubber | 60 ±5 |
| RST14-S | Black | Yes | Approx. 1 Stopper | Natural Rubber | 60 ±5 |
| RST15-H | Black | Yes | Approx. 1 Stopper | Natural Rubber | 60 ±5 |
| RST15-H2 | Black | Yes | Approx. 1 Stopper | Natural Rubber | 60 ±5 |
| RST15-S | Black | Yes | Approx. 1 Stopper | Natural Rubber | 60 ±5 |
| RST16-H | Black | Yes | Approx. 1 Stopper | Natural Rubber | 60 ±5 |
| RST16-H2 | Black | Yes | Approx. 1 Stopper | Natural Rubber | 60 ±5 |
| RST16-S | Black | Yes | Approx. 1 Stopper | Natural Rubber | 60 ±5 |
| RST5A-H | Black | Yes | Approx. 21 Stoppers | Natural Rubber | 60 ±5 |
| RST5A-H2 | Black | Yes | Approx. 21 Stoppers | Natural Rubber | 60 ±5 |
| RST5A-S | Black | Yes | Approx. 21 Stoppers | Natural Rubber | 60 ±5 |
| RST7A-H | Black | Yes | Approx. 13 Stoppers | Natural Rubber | 60 ±5 |
| RST7A-H2 | Black | Yes | Approx. 13 Stoppers | Natural Rubber | 60 ±5 |
| RST7A-S | Black | Yes | Approx. 13 Stoppers | Natural Rubber | 60 ±5 |
| RST8A-H | Black | Yes | Approx. 10 Stoppers | Natural Rubber | 60 ±5 |
| RST8A-H2 | Black | Yes | Approx. 10 Stoppers | Natural Rubber | 60 ±5 |
| RST000-H | Black | Yes | Approx. 170 Stoppers | Natural Rubber | 60 ±5 |
| RST000-S | Black | Yes | Approx. 170 Stoppers | Natural Rubber | 60 ±5 |
| RST8A-S | Black | Yes | Approx. 10 Stoppers | Natural Rubber | 60 ±5 |
| RST00-H | Black | Yes | Approx. 90 Stoppers | Natural Rubber | 60 ±5 |
| RST9A-H | Black | Yes | Approx. 9 Stoppers | Natural Rubber | 60 ±5 |
| RST9A-H2 | Black | Yes | Approx. 9 Stoppers | Natural Rubber | 60 ±5 |
| RST00-S | Black | Yes | Approx. 90 Stoppers | Natural Rubber | 60 ±5 |
| RST9A-S | Black | Yes | Approx. 9 Stoppers | Natural Rubber | 60 ±5 |
| RST0-H | Black | Yes | Approx. 63 Stoppers | Natural Rubber | 60 ±5 |
| RST0-H2 | Black | Yes | Approx. 63 Stoppers | Natural Rubber | 60 ±5 |
| RST0-S | Black | Yes | Approx. 63 Stoppers | Natural Rubber | 60 ±5 |
| RST10A-H | Black | Yes | Approx. 7 Stoppers | Natural Rubber | 60 ±5 |
| RST10A-H2 | Black | Yes | Approx. 7 Stoppers | Natural Rubber | 60 ±5 |
| RST10A-S | Black | Yes | Approx. 7 Stoppers | Natural Rubber | 60 ±5 |
| RST10-H | Black | Yes | Approx. 8 Stoppers | Natural Rubber | 60 ±5 |
| RST10-H2 | Black | Yes | Approx. 8 Stoppers | Natural Rubber | 60 ±5 |
| RST10-S | Black | Yes | Approx. 8 Stoppers | Natural Rubber | 60 ±5 |
| RST11A-H | Black | Yes | Approx. 6 Stoppers | Natural Rubber | 60 ±5 |
| RST11A-H2 | Black | Yes | Approx. 6 Stoppers | Natural Rubber | 60 ±5 |
| RST11A-S | Black | Yes | Approx. 6 Stoppers | Natural Rubber | 60 ±5 |
| RST11-H | Black | Yes | Approx. 6 Stoppers | Natural Rubber | 60 ±5 |
| RST11-H2 | Black | Yes | Approx. 6 Stoppers | Natural Rubber | 60 ±5 |
| RST11-S | Black | Yes | Approx. 6 Stoppers | Natural Rubber | 60 ±5 |
| RST13-H | Black | Yes | Approx. 4 Stoppers | Natural Rubber | 60 ±5 |
| RST13-H2 | Black | Yes | Approx. 4 Stoppers | Natural Rubber | 60 ±5 |
| RST13-S | Black | Yes | Approx. 4 Stoppers | Natural Rubber | 60 ±5 |
| RST1-H | Black | Yes | Approx. 52 Stoppers | Natural Rubber | 60 ±5 |
| RST1-H2 | Black | Yes | Approx. 52 Stoppers | Natural Rubber | 60 ±5 |
| RST1-S | Black | Yes | Approx. 52 Stoppers | Natural Rubber | 60 ±5 |
| RST2-H | Black | Yes | Approx. 45 Stoppers | Natural Rubber | 60 ±5 |
| RST2-H2 | Black | Yes | Approx. 45 Stoppers | Natural Rubber | 60 ±5 |
| RST2-S | Black | Yes | Approx. 45 Stoppers | Natural Rubber | 60 ±5 |
| RST3-H | Black | Yes | Approx. 33 Stoppers | Natural Rubber | 60 ±5 |
| RST3-H2 | Black | Yes | Approx. 33 Stoppers | Natural Rubber | 60 ±5 |
| RST3-S | Black | Yes | Approx. 33 Stoppers | Natural Rubber | 60 ±5 |
| RST4-H | Black | Yes | Approx. 28 Stoppers | Natural Rubber | 60 ±5 |
| RST4-H2 | Black | Yes | Approx. 28 Stoppers | Natural Rubber | 60 ±5 |
| RST4-S | Black | Yes | Approx. 28 Stoppers | Natural Rubber | 60 ±5 |
| RST5-H | Black | Yes | Approx. 24 Stoppers | Natural Rubber | 60 ±5 |
| RST5-H2 | Black | Yes | Approx. 24 Stoppers | Natural Rubber | 60 ±5 |
| RST5-S | Black | Yes | Approx. 24 Stoppers | Natural Rubber | 60 ±5 |
| RST6A-H | Black | Yes | Approx. 16 Stoppers | Natural Rubber | 60 ±5 |
| RST6A-H2 | Black | Yes | Approx. 16 Stoppers | Natural Rubber | 60 ±5 |
| RST6A-S | Black | Yes | Approx. 16 Stoppers | Natural Rubber | 60 ±5 |
| RST6-H | Black | Yes | Approx. 18 Stoppers | Natural Rubber | 60 ±5 |
| RST6-H2 | Black | Yes | Approx. 18 Stoppers | Natural Rubber | 60 ±5 |
| RST6-S | Black | Yes | Approx. 18 Stoppers | Natural Rubber | 60 ±5 |
| RST7-H | Black | Yes | Approx. 13 Stoppers | Natural Rubber | 60 ±5 |
| RST7-H2 | Black | Yes | Approx. 13 Stoppers | Natural Rubber | 60 ±5 |
| RST7-S | Black | Yes | Approx. 13 Stoppers | Natural Rubber | 60 ±5 |
| RST8-H | Black | Yes | Approx. 10 Stoppers | Natural Rubber | 60 ±5 |
| RST8-H2 | Black | Yes | Approx. 10 Stoppers | Natural Rubber | 60 ±5 |
| RST8-S | Black | Yes | Approx. 10 Stoppers | Natural Rubber | 60 ±5 |
| RST9-H | Black | Yes | Approx. 9 Stoppers | Natural Rubber | 60 ±5 |
| RST9-H2 | Black | Yes | Approx. 9 Stoppers | Natural Rubber | 60 ±5 |
| RST9-S | Black | Yes | Approx. 9 Stoppers | Natural Rubber | 60 ±5 |
| RST13A-S | Black | Yes | Approx. 4 Stoppers | Natural Rubber | 60 ±5 |
The Natural Rubber Stoppers from United Scientific are a laboratory staple, engineered to provide an airtight and secure seal for flasks, test tubes, and carboys. Crafted from premium black natural rubber, these stoppers are designed for long-term pliability, ensuring they don't become brittle or lose their grip even after repeated use. Each stopper is clearly marked with its size in raised figures for quick identification. These are ideal for use with non-aggressive or concentrated solutions and feature a low sulfur content. Available in solid, one-hole, and two-hole versions, they provide the versatility needed for everything from simple storage to complex distillation setups.
Starting at from $10.25 Sale $6.16
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