# 12 RW — Hypodermic needle gauge dimensions (OD, ID, wall thickness, dead volume)

For 12 RW, nominal o.d. (mm) is 2.77; nominal i.d. (mm) is 2.16; wall thickness (mm) is .305, verified against its source on 2026-08-27.

- **Gauge number:** 12 RW _(verified: appears in the quote below)_
- **Nominal O.D. (mm):** 2.77 _(verified: appears in the quote below)_
- **Nominal I.D. (mm):** 2.16 _(verified: appears in the quote below)_
- **Wall thickness (mm):** .305 _(verified: appears in the quote below)_

## What the source says

> 12     RW   2.77   2.74/2.79   .305   2.16     2.11/2.21

## Source

- https://nesmalltube.com/wp-content/uploads/2025/06/Metric_Chart_Web.pdf

Last verified: 2026-08-27. Review by: 2029-08-26.
Part of [Hypodermic needle gauge dimensions (OD, ID, wall thickness, dead volume)](https://referencesource.org/syringe-needle-gauge-dimensions/).