Rubber Bung Sizes

2021-04-26 · Stoppers & Plugs

Rubber Bung Sizes

How often does it happen You need to buy rubber bungs, but you have no idea about the rubber bung sizes. The sizes vary in millimeters; you can’t quickly determine the correct size from the naked eye. For instance, rubber bungs of size 0 have a bottom-side diameter of 13mm, while the bungs of size 1 have a bottom-side diameter of 14mm; it’s hard to tell the difference. If you go ahead and purchase a comparable size, you may get stuck with rubber bungs of the wrong dimensions. You might want to avoid that situation altogether. In this post, we will talk about the different rubber bung sizes and how you can pick the right one.

Let’s start with different sizes that exist in the market. You can refer to this chart to match the dimensions of your test tube with. Remember, you want a close match of the test tube diameter you measure with the bottom side diameter mentioned in the chart. The next step is to measure the size of the stopper:

1. Measure the inner diameter of the test tube using calipers
2. Refer to the rubber bung selection chart and select the range of size that best fits the test-tube
3. If more than one size works, select the correct size based on depth range and inner diameter

This test which would take a couple of minutes, will save you money and effort that you would otherwise spend buying rubber bungs. In addition, you can do this test right at your lab! All you need is a set of calipers. That’s it, we hope you can now find suitable rubber bung sizes for your equipment without much of a hassle.

All dimensions are in mm

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.

T-shaped stopper — original A, B, C, D and E dimensions — A recessed RST variant is illustrated. The head remains closed. Check E and the approved section for the selected part.

Rubber Silicone Plugs(T-shaped-RST) — product view — Illustrative product rendering. Refer to the selected part drawing and table for dimensions.

PartNo.	A（mm）	B（mm）	C（mm）	D（mm）
RST2.5-5.5-5.3	2.5	5.5	5.3	2
RST2.7-5.5-5	2.7	5.5	5	2
RST3-4.3-4.5	3	4.3	4.5	0.8
RST3-7-7	3	7	7	2.2
RST3.3-6.5-6	3.3	6.5	6	1.5
RST3.5-6.5-6	3.5	6.5	6	2
RST3.8-7-10.5	3.8	7	10.5	1.5
RST3.8-7-7	3.8	7	7	1.5
RST3.8-7-6	3.8	7	6	1.5
RST4-7.5-6	4	7.5	6	2
RST4-9.5-7	4	9.5	7	2.5
RST4.3-8-6	4.3	8	6	1.5
RST4.5-7.5-6	4.5	7.5	6	2
RST4.8-6.8-3.6	4.8	6.8	3.6	0.9
RST4.8-9-7	4.8	9	7	1.5

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.

Tapered cork — Diameter A, Diameter B and Height — Tapered profile reference. Use Diameter A, Diameter B and Height from the selected row.

Rubber Corks(Tapered-RSA) — product view — Illustrative product rendering. Refer to the selected part drawing and table for dimensions.

Part No.	Diameter A	Diameter B	Height	Materials
RSA1.6-0.4-15.9	1.6	0.4	15.9	Silicone
RSA2-0.5-19.1	2	0.5	19.1	Silicone
RSA3.2-0.8-15.9	3.2	0.8	15.9	Silicone
RSA3.2-1.6-15.9	3.2	1.6	15.9	Silicone
RSA4.8-1.6-15.9	4.8	1.6	15.9	Silicone
RSA4.8-1.6-19.1	4.8	1.6	19.1	Silicone
RSA5.5-1.2-38.1	5.5	1.2	38.1	Silicone
RSA6.4-3.2-19.1	6.4	3.2	19.1	Silicone
RSA6.4-3.2-25.4	6.4	3.2	25.4	Silicone
RSA8.7-4.8-15.9	8.7	4.8	15.9	Silicone
RSA8.7-4.8-25.4	8.7	4.8	25.4	Silicone
RSA9.2-6.2-12.8	9.2	6.2	12.8	Silicone
RSA9.5-6.5-18.5	9.5	6.5	18.5	Silicone
RSA11-8.5-17.5	11	8.5	17.5	Silicone
RSA11.5-6.5-25	11.5	6.5	25	Silicone

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.

Silicone Plugs(Undercut-RSB) — product view — Illustrative product rendering. Refer to the selected part drawing and table for dimensions.

Part No.	A (mm)	B (mm)	C (mm)	D (mm)	E (mm)
RSB2.5-6-3	2.5	6	3	1.5	0
RSB3-7-3	3	7	3	2	0
RSB3.5-7.5-3	3.5	7.5	3	2	0
RSB3.6-7.5-6	3.6	7.5	6	2	0
RSB4-8-3	4	8	3	2	0
RSB4.5-8.5-3	4.5	8.5	3	2	2
RSB5-9-3	5	9	3	2	2.5
RSB5.5-9.5-3	5.5	9.5	3	2	3
RSB6-10-4	6	10	4	2	3.5
RSB6.5-10.5-4	6.5	10.5	4	2	4
RSB6.5-12-8	6.5	12	8	2	0
RSB6.7-8.7-5.3	6.7	8.7	5.3	1.3	4.1
RSB7-11-4	7	11	4	2	4.5
RSB7.5-11.5-4	7.5	11.5	4	2	5
RSB8-12-4	8	12	4	2	5.5

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.

T-shaped stopper — original A, B, C and D dimensions — Solid T-shaped profile reference. Dimensions A–D follow the selected part drawing.

Silicone Stoppers(T shape) — product view — Illustrative product rendering. Refer to the selected part drawing and table for dimensions.

Part No.	A (mm)	B (mm)	C (mm)	D (mm)	Materials
RSD2.7-5.5-5	2.7	5.5	5	2	Rubber, Silicone
RSD3-7-7	3	7	7	2.2	Rubber, Silicone
RSD3.3-6.5-6	3.3	6.5	6	1.5	Rubber, Silicone
RSD3.5-6.5-6	3.5	6.5	6	2	Rubber, Silicone
RSD3.8-7-6	3.8	7	6	1.5	Rubber, Silicone
RSD4-9.5-7	4	9.5	7	2.5	Rubber, Silicone
RSD4.3-8-6	4.3	8	6	1.5	Rubber, Silicone
RSD4.5-7.5-6	4.5	7.5	6	2	Rubber, Silicone
RSD4.8-9-7	4.8	9	7	1.5	Rubber, Silicone
RSD5-12-8	5	12	8	2.8	Rubber, Silicone
RSD5.3-9.5-7	5.3	9.5	7	1.5	Rubber, Silicone
RSD5.5-8.5-7	5.5	8.5	7	2	Rubber, Silicone
RSD5.8-10-8	5.8	10	8	2	Rubber, Silicone
RSD6-13-8	6	13	8	3.5	Rubber, Silicone
RSD6.3-10.5-8	6.3	10.5	8	2	Rubber, Silicone

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Rubber Bung Sizes