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

For 20 RW, nominal o.d. (mm) is 0.91; nominal i.d. (mm) is 0.61; wall thickness (mm) is .152, verified against its source on 2026-08-27.

- **Gauge number:** 20 RW _(verified: appears in the quote below)_
- **Nominal O.D. (mm):** 0.91 _(verified: appears in the quote below)_
- **Nominal I.D. (mm):** 0.61 _(verified: appears in the quote below)_
- **Wall thickness (mm):** .152 _(verified: appears in the quote below)_

## What the source says

> 20     RW   0.91   0.90/0.91   .152   0.61   0.58/0.62

## 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/).