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General product information only, not medical advice. Which tube a patient receives, and whether one is needed, is decided by the treating clinician. This page is for people reading product catalogues, device records or supply specifications.
“Grommet sizes” in a medical context means the labelled inner diameter (lumen), in millimetres, of a tympanostomy (ear) tube. The labelled diameters in FDA’s device database run from 0.76 mm to 1.52 mm, and 1.14 mm is the value that appears most often in the examples below. This page is about ear-tube grommets only; it does not cover fabric, banner or eyelet grommets, which use a different numbering system.
Grommet size chart (ear tube inner diameter)
The chart lists manufacturer-labelled values copied from device records in the U.S. FDA UDI database (openFDA, product code ETD, 1,552 records; checked 30 October 2026). Each row names the manufacturer’s own product description. It is a set of examples, not a complete catalogue.
| Inner diameter | Style named in the record | Manufacturer record | Other labelled dimension |
|---|---|---|---|
| 0.76 mm | Moretz Tytan | Medtronic 1056108 | Lumen 0.76 mm |
| 0.76 mm | Tiny TEF vent tube (fluoroplastic) | Grace Medical 520-152 | 0.76 mm ID |
| 0.89 mm | Straight vent tube, Pacific (fluoroplastic) | Gyrus ACMI 70141036 | 0.89 mm ID |
| 1.02 mm | Paparella | Medtronic 14521 and 24442 | Lumen 1.02 mm |
| 1.02 mm | Shepard grommet with tab | Grace Medical 520-031 | 1.02 mm ID |
| 1.14 mm | Armstrong beveled grommet | Medtronic 1010056 | Lumen 1.14 mm |
| 1.14 mm | Shepard grommet (wire) | Medtronic MV16501 | “1.14” in the description |
| 1.14 mm | Armstrong X beveled grommet | Grace Medical 525-201 | 1.14 mm ID |
| 1.14 mm | Armstrong V | Medtronic 1056031 | “1.14X4.5”: length 4.5 mm |
| 1.14 mm | Armstrong | Medtronic 1010040 | Length 7.0 mm |
| 1.14 mm | Straight tube | Gyrus 145007-ENT | 1.14 mm ID x 12 mm |
| 1.14 mm | Goode T-Tube | Medtronic 1056016 | Length 6.0 mm |
| 1.14 mm | Goode T-Tube | Medtronic 1056019 | Length 9.0 mm |
| 1.27 mm | Sheehy button | Medtronic MV13301 | Lumen 1.27 mm |
| 1.27 mm | Modified collar button | Grace Medical 510-241 | 1.27 mm ID |
| 1.52 mm | Paparella Type 2 | Medtronic MV1076 | “1.52MM” in the description |
Check your product’s labelling. Sizes, models and part numbers change, and the label and instructions for use that come with the device are the authority for that product.
How to read the chart
Ear-tube size is given as the inner diameter of the tube’s lumen in millimetres. Length is listed mainly for the T-type and for straight tubes (rows above show 4.5 to 12 mm). Style names such as Armstrong, Shepard or Sheehy are manufacturer or designer names, not size grades: the same 1.14 mm diameter appears under several of them.
The manufacturer-entered descriptions use four shape words: grommet (Armstrong, Shepard, Pope, Paparella), collar button (Sheehy, Friedman), bobbin (Reuter) and T-tube (Goode). Materials named in the descriptions include silicone, fluoroplastic, titanium, polyethylene and hydroxylapatite. Every ETD record examined for this chart was labelled single use.
How the device is classified
FDA defines a tympanostomy tube as “a device that is intended to be implanted for ventilation or drainage of the middle ear” and classifies it as Class II under 21 CFR 874.3880 (checked 30 October 2026). openFDA lists these product codes, which are useful search terms in AccessGUDID:
- ETD: Tube, Tympanostomy (Class II, 21 CFR 874.3880).
- LBL: Tube, Tympanostomy, Porous Polyethylene (Class II, 21 CFR 874.3880).
- KQL: Tube, Tympanostomy With Semi-Permeable Membrane (Class II, 21 CFR 874.3930).
The device-record vocabulary (GMDN) treats “myringotomy tube”, “grommet” and “aural vent tube” as other names for a tympanostomy tube. No ISO or ASTM ear-tube size or colour-code standard is cited here; sizes are what each manufacturer labels. In AccessGUDID, one example, the Goode T-Tube (DI 00681490031837), is recorded with a 1.14 mm inner diameter, 9.0 mm length, MR Conditional status and single-use packaging.
Equivalence notes
- Millimetres, not gauge or French. The ear-tube records above use mm of inner diameter. Do not convert to French (a different unit; see G-tube types for another tube family) or wire gauge.
- “Grommet” also means a fabric or metal eyelet. Banner and curtain grommets are numbered by hole size and are unrelated to the medical device.
- Same name, different devices. “Tympanostomy tube”, “myringotomy tube”, “ear tube” and “grommet” appear in the device record vocabulary for the same product category.
Common mix-ups
- Reading a style name (Armstrong, Sheehy) as a size. Look for the mm value in the description.
- Treating the lumen as the outside diameter. The records quote inner diameter or lumen.
- Confusing ear tubes with other tubes in the supply catalogue, such as the instruments in ENT surgical instruments or tubes in a surgical pack.
FAQ
What are the ear tube types?
In FDA device records, ear tubes appear as grommets, collar buttons, bobbins and T-tubes, under product codes ETD, LBL and KQL. Which type is used for a patient is a clinical decision.
What are the grommet types?
Records name grommet styles including Armstrong (beveled), Shepard (with tab or wire), Pope and Paparella. In the examples above, these were labelled from 0.76 to 1.52 mm inner diameter.
What are the tympanostomy tube types?
FDA lists three product codes, all Class II: ETD (tympanostomy tube), LBL (porous polyethylene) and KQL (with a semi-permeable membrane).
T-tube vs grommet: what is the difference?
Both are tympanostomy tubes under the same FDA product code (ETD). Grommet records in the chart give a diameter, while the Goode T-Tube records give both a 1.14 mm inner diameter and a length (6.0 or 9.0 mm). The FDA records cited here do not compare how long either stays in place, so this page makes no such comparison.
Sources
- 21 CFR 874.3880, Tympanostomy tube, Legal Information Institute, https://www.law.cornell.edu/cfr/text/21/874.3880, checked 30 October 2026.
- openFDA device classification API, product codes ETD, LBL, KQL, https://api.fda.gov/device/classification.json, checked 30 October 2026.
- openFDA UDI API, product code ETD (1,552 records; manufacturer descriptions in the chart), https://api.fda.gov/device/udi.json, checked 30 October 2026.
- AccessGUDID record for Goode T-Tube, DI 00681490031837, https://accessgudid.nlm.nih.gov/devices/00681490031837, checked 30 October 2026.
Related reading: a different tube-sizing reference is NG tube sizes for adults.
