Silicone stopper size chart
Use a silicone stopper size chart to compare the dimensions of a replacement with the opening it must seal. Begin with the vessel neck, not the apparent size of a worn stopper. Different suppliers can use different size labels, so the stated dimensions and units are the basis for comparison.
For a tapered stopper, the small end must enter the opening while the larger section provides seating at the intended depth. Check the top diameter, bottom diameter and height together. Leave enough of the stopper exposed for the planned removal method, and assess the fit without forcing the vessel neck.
Stoppers are available with and without holes. A solid stopper closes the body, while a bored stopper needs a matching tube, probe or fitting to complete the assembly. Include the passage diameter and position in the size comparison, then choose the compound for the liquid, gas and temperature involved.
Stopper & Plug Size Catalog
Compare four stopper profiles and check the selected part dimensions against your opening and available depth. Each profile has its own drawing and dimension meanings.
Custom colors are available to your Pantone color code. Include the code in your inquiry.
RST T-Shaped Plugs
Match stem diameter A, flange diameter B, stem length C and flange thickness D. E refers to the underside recess; use the selected row and approved drawing to confirm the actual profile.

RSA Tapered Corks
Compare large-end diameter A, small-end diameter B and Height, in mm. The mating bore and required seating depth determine where the taper contacts the opening.

RSB Undercut Plugs
Compare neck diameter A, flange diameter B, flange-to-lip distance C and flange thickness D. Check panel thickness and rear clearance. E refers to the underside recess.

RSD T-Shaped Stoppers
Compare stem diameter A, flange diameter B, stem length C and head thickness D, in mm. Check the seating surface and available depth as well as the hole diameter.

Need a different fit? Share the opening dimensions, mating profile and intended use for a custom size.
Discuss Your RequirementsProduct specifications
- Selection focus
- Replacement silicone stopper matched by dimensions rather than supplier size label.
- Taper fit
- Compare both end diameters, height, insertion depth and exposed removal area.
- Body options
- Choose a solid stopper or a bore fitted around a tube or probe.
- Passage dimensions
- Specify diameter and position of each required opening.
- Contact conditions
- Select the silicone formulation for the contents and temperature.
Need a quote or a custom part?
Send your requirements, drawings or samples to discuss standard and custom silicone rubber parts.
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