Working conditions
Identify temperature, contact fluids and repeated movement.

Custom manufacturing example · Industrial equipment various NBR dust-proof stoppers/rubber caps
CUSTOM RUBBER & SILICONE MANUFACTURING
A custom component for your assembly.
Define the mating surfaces, dimensions and working conditions. ETOL manufactures the part to the agreed design and material.
Share the part, its application and your estimated quantity.

Selected for the contact, temperature and movement
Define the visible surfaces and intended color
Develop holes, lips and walls around the mating parts
Match the attachment and installation method
NBR dust-proof stoppers provide custom closures for industrial equipment openings that need protection from loose contamination. Their usefulness continues through maintenance: the opening must be exposed, worked on, and closed again without carrying accumulated debris into the equipment. The stopper shape should support that sequence as well as fit the hole.
An accessible removal surface helps an operator lift the stopper without scraping dirt from its head into the opening. Before removal, clean the surrounding area and establish a clean place for the part while the equipment is open. If several closures are removed together, maintain their position identity where the dimensions or materials differ. Similar looking caps and inserted stoppers should remain associated with their own mating surfaces.
Select the NBR formulation for the local contact conditions, including any cleaning fluid used during servicing. Refit only after the opening and stopper contact surfaces have been inspected. The part should return to its intended depth without folding or rocking. If the equipment requires a defined environmental seal, evaluate the installed closure under those conditions rather than relying on its dust covering purpose alone.
Photos illustrate structure or material appearance only. The stopper shape should support that sequence as well as fit the hole. ETOL directly manufactures custom-shaped silicone and rubber parts to your requirements.
FIND THE RIGHT FIT
Choose a blind-hole, tapered, undercut or solid T-shaped profile, then compare its dimensions with the opening and available seating depth. Each profile has its own drawing and dimension meanings.
155 T-shaped plug sizes. Match shank diameter A, head diameter B, shank length C and head thickness D. E is the bottom blind-hole diameter; E = 0 indicates a solid shank.
| P/N | A | B | C | D | E | Unit |
|---|---|---|---|---|---|---|
| RST2.5-5.5-5.3 | 2.5 | 5.5 | 5.3 | 2 | 0 | mm |
| RST2.7-5.5-5 | 2.7 | 5.5 | 5 | 2 | 0 | mm |
| RST3-4.3-4.5 | 3 | 4.3 | 4.5 | 0.8 | 0 | mm |
| RST3-7-7 | 3 | 7 | 7 | 2.2 | 0 | mm |
| RST3.3-6.5-6 | 3.3 | 6.5 | 6 | 1.5 | 0 | mm |
| RST3.5-6.5-6 | 3.5 | 6.5 | 6 | 2 | 0 | mm |
| RST3.8-7-10.5 | 3.8 | 7 | 10.5 | 1.5 | 0 | mm |
| RST3.8-7-7 | 3.8 | 7 | 7 | 1.5 | 0 | mm |
| RST3.8-7-6 | 3.8 | 7 | 6 | 1.5 | 0 | mm |
| RST4-7.5-6 | 4 | 7.5 | 6 | 2 | 0 | mm |
| RST4-9.5-7 | 4 | 9.5 | 7 | 2.5 | 0 | mm |
| RST4.3-8-6 | 4.3 | 8 | 6 | 1.5 | 0 | mm |
| RST4.5-7.5-6 | 4.5 | 7.5 | 6 | 2 | 0 | mm |
| RST4.8-6.8-3.6 | 4.8 | 6.8 | 3.6 | 0.9 | 0 | mm |
| RST4.8-9-7 | 4.8 | 9 | 7 | 1.5 | 0 | mm |
70 tapered stopper sizes. Compare the large-end diameter A, small-end diameter B and overall height with the opening and intended insertion depth.
| P/N | A | B | Height | Color | Material | Unit |
|---|---|---|---|---|---|---|
| RSA1.6-0.4-15.9 | 1.6 | 0.4 | 15.9 | Transparent | Silicone | mm |
| RSA2-0.5-19.1 | 2 | 0.5 | 19.1 | Transparent | Silicone | mm |
| RSA3.2-0.8-15.9 | 3.2 | 0.8 | 15.9 | Transparent | Silicone | mm |
| RSA3.2-1.6-15.9 | 3.2 | 1.6 | 15.9 | Transparent | Silicone | mm |
| RSA4.8-1.6-15.9 | 4.8 | 1.6 | 15.9 | Transparent | Silicone | mm |
| RSA4.8-1.6-19.1 | 4.8 | 1.6 | 19.1 | Transparent | Silicone | mm |
| RSA5.5-1.2-38.1 | 5.5 | 1.2 | 38.1 | Transparent | Silicone | mm |
| RSA6.4-3.2-19.1 | 6.4 | 3.2 | 19.1 | Transparent | Silicone | mm |
| RSA6.4-3.2-25.4 | 6.4 | 3.2 | 25.4 | Transparent | Silicone | mm |
| RSA8.7-4.8-15.9 | 8.7 | 4.8 | 15.9 | Transparent | Silicone | mm |
| RSA8.7-4.8-25.4 | 8.7 | 4.8 | 25.4 | Transparent | Silicone | mm |
| RSA9.2-6.2-12.8 | 9.2 | 6.2 | 12.8 | Transparent | Silicone | mm |
| RSA9.5-6.5-18.5 | 9.5 | 6.5 | 18.5 | Transparent | Silicone | mm |
| RSA11-8.5-17.5 | 11 | 8.5 | 17.5 | Transparent | Silicone | mm |
| RSA11.5-6.5-25 | 11.5 | 6.5 | 25 | Transparent | Silicone | mm |
50 undercut plug sizes with a retaining lip. A is the neck diameter and C is the distance from the underside of the head to the upper face of the lip. E = 0 indicates a solid shank.
| P/N | A | B | C | D | E | Unit |
|---|---|---|---|---|---|---|
| RSB2.5-6-3 | 2.5 | 6 | 3 | 1.5 | 0 | mm |
| RSB3-7-3 | 3 | 7 | 3 | 2 | 0 | mm |
| RSB3.5-7.5-3 | 3.5 | 7.5 | 3 | 2 | 0 | mm |
| RSB3.6-7.5-6 | 3.6 | 7.5 | 6 | 2 | 0 | mm |
| RSB4-8-3 | 4 | 8 | 3 | 2 | 0 | mm |
| RSB4.5-8.5-3 | 4.5 | 8.5 | 3 | 2 | 2 | mm |
| RSB5-9-3 | 5 | 9 | 3 | 2 | 2.5 | mm |
| RSB5.5-9.5-3 | 5.5 | 9.5 | 3 | 2 | 3 | mm |
| RSB6-10-4 | 6 | 10 | 4 | 2 | 3.5 | mm |
| RSB6.5-10.5-4 | 6.5 | 10.5 | 4 | 2 | 4 | mm |
| RSB6.5-12-8 | 6.5 | 12 | 8 | 2 | 0 | mm |
| RSB6.7-8.7-5.3 | 6.7 | 8.7 | 5.3 | 1.3 | 4.1 | mm |
| RSB7-11-4 | 7 | 11 | 4 | 2 | 4.5 | mm |
| RSB7.5-11.5-4 | 7.5 | 11.5 | 4 | 2 | 5 | mm |
| RSB8-12-4 | 8 | 12 | 4 | 2 | 5.5 | mm |
30 solid T-shaped stopper sizes. Compare shank diameter A and length C with the opening; head diameter B and thickness D define the top flange.
| P/N | A | B | C | D | Color | Material | Unit |
|---|---|---|---|---|---|---|---|
| RSD2.7-5.5-5 | 2.7 | 5.5 | 5 | 2 | Black, White | Silicone | mm |
| RSD3-7-7 | 3 | 7 | 7 | 2.2 | Black, White | Silicone | mm |
| RSD3.3-6.5-6 | 3.3 | 6.5 | 6 | 1.5 | Black, White | Silicone | mm |
| RSD3.5-6.5-6 | 3.5 | 6.5 | 6 | 2 | Black, White | Silicone | mm |
| RSD3.8-7-6 | 3.8 | 7 | 6 | 1.5 | Black, White | Silicone | mm |
| RSD4-9.5-7 | 4 | 9.5 | 7 | 2.5 | Black, White | Silicone | mm |
| RSD4.3-8-6 | 4.3 | 8 | 6 | 1.5 | Black, White | Silicone | mm |
| RSD4.5-7.5-6 | 4.5 | 7.5 | 6 | 2 | Black, White | Silicone | mm |
| RSD4.8-9-7 | 4.8 | 9 | 7 | 1.5 | Black, White | Silicone | mm |
| RSD5-12-8 | 5 | 12 | 8 | 2.8 | Black, White | Silicone | mm |
| RSD5.3-9.5-7 | 5.3 | 9.5 | 7 | 1.5 | Black, White | Silicone | mm |
| RSD5.5-8.5-7 | 5.5 | 8.5 | 7 | 2 | Black, White | Silicone | mm |
| RSD5.8-10-8 | 5.8 | 10 | 8 | 2 | Black, White | Silicone | mm |
| RSD6-13-8 | 6 | 13 | 8 | 3.5 | Black, White | Silicone | mm |
| RSD6.3-10.5-8 | 6.3 | 10.5 | 8 | 2 | Black, White | Silicone | mm |
Need a different fit? Share the opening dimensions, mating profile and intended use for a custom size.
Identify key dimensions, mating surfaces and quantity
Agree the compound and manufacturing approach
Review the fit and agreed requirements in the assembly
Manufacture and check against the approved requirements
Identify temperature, contact fluids and repeated movement.
Consider hardness together with wall thickness and support.
Check access, mating dimensions and the fitting sequence.
Yes. Show the receiving opening, contact surfaces and clearance limits. We can review the dimensions and retaining features around the intended fit.
Agree the critical dimensions, material, hardness, visible surfaces and sample requirements. Explain how the part is installed and which interfaces control its function.
A sample can help explain the structure. Compare it with the assembly because wear, swelling or compression may have changed its original dimensions.
The material, part geometry, tooling, quantity and finishing affect the quotation. Include the intended batch size and delivery destination when describing your requirements.
DISCUSS THIS COMPONENT
Share the fit, operating conditions and quantity with our manufacturing team.