AN Sizing
AN fittings are commonly used in motorsport and modified street cars. AN Fitting sizing corresponds to the outer diameter of the metal tube that the fitting is used with, and incrementally increases by 1/16″. This means that in theory AN-8 is 8/16″ or 1/2″. In reality, the large variation of AN fitting types, and hose types means that these numbers are often quite different depending on which part of the fitting we are meauring.
To quickly be able to identify the sizing of an existing fitting the following guide has been made.
The thread size is also included.
Male AN Fitting Sizing
To determine the size of an AN male fitting, measure the outer diameter of the threaded section, including the threads, or measure the top section below the flare.
| AN Size | Thread Size | Dimension in Threads | Outer Dimension |
| -02 | 5/16-24 SAE | ~6.2mm | ~7.9mm |
| -03 | 3/8-24 SAE | ~7.7mm | ~9.4mm |
| -04 | 7/16-20 SAE | ~9.1mm | ~11.8mm |
| -05 | 1/2-20 SAE | ~10.2mm | ~12.7mm |
| -06 | 9/16-18 SAE | ~11.6mm | ~14.2mm |
| -08 | 3/4-16 SAE | ~16.6mm | ~19.0mm |
| -10 | 7/8-14 SAE | ~19.5mm | ~22.3mm |
| -12 | 1-1/16-12 SAE | ~23.8mm | ~26.9mm |
| -16 | 1-5/16-12 SAE | ~30.2mm | ~33.3mm |
| -20 | 1-5/8-12 SAE | ~38.2mm | ~41.4mm |
Female AN Fitting Sizing
To determine the size of an AN female fitting, measure the inner diameter of the threaded section.
| AN Size | Thread Size | Inner Dimension |
| -02 | 5/16-24 SAE | ~6.9mm |
| -03 | 3/8-24 SAE | ~8.6mm |
| -04 | 7/16-20 SAE | ~9.9mm |
| -05 | 1/2-20 SAE | ~11.4mm |
| -06 | 9/16-18 SAE | ~12.9mm |
| -08 | 3/4-16 SAE | ~17.5mm |
| -10 | 7/8-14 SAE | ~20.6mm |
| -12 | 1-1/16-12 SAE | ~24.9mm |
| -16 | 1-5/16-12 SAE | ~31.2mm |
| -20 | 1-5/8-12 SAE | ~39.1mm |
An Hose Sizing
AN Hose is always measured using the internal diameter of the hose. Some manufacturing differences may mean that the exact measurements may differ depending on the hose type and manufacturer. Ensure that you are using the correct hose ends for the type of hose you have selected.
Braided Rubber Hose
| AN Size | Hose ID (metric) | Hose ID (imperial) |
| -04 | ~5.4mm | ~7/32″ |
| -05 | ~6.4mm | ~1/4″ |
| -06 | ~8.7mm | ~11/32″ |
| -08 | ~11.1mm | ~7/16″ |
| -10 | ~14.2mm | ~9/16″ |
| -12 | ~17.4mm | ~11/16″ |
| -16 | ~22.2mm | ~7/8″ |
| -20 | ~28.5mm | ~1-1/8″ |
PTFE (Teflon) Hose
| AN Size | Hose ID (metric) | Hose ID (imperial) |
| -03 | ~3.5mm | ~9/64″ |
| -04 | ~4.8mm | ~3/16″ |
| -06 | ~8.1mm | ~21/64″ |
| -08 | ~10.6mm | ~27/64″ |
| -10 | ~12.9mm | ~33/64″ |
| -12 | ~16.2mm | ~41/64″ |
| -16 | ~22.3mm | ~7/8″ |
| -20 | ~28.4mm | ~1-1/8″ |
AN Tube Sizing
AN Tube is measured on the outer dimension. Due to the outer dimension being the critical dimension, the inner dimension can vary due to changes in wall thickness.
| AN Size | Tube OD (metric) | Tube OD (imperial) |
| -02 | 1.57mm | 1/16″ |
| -03 | 4.78mm | 3/16″ |
| -04 | 6.35mm | 1/4″ |
| -05 | 7.95mm | 5/16″ |
| -06 | 9.53mm | 3/8″ |
| -08 | 12.7mm | 1/2″ |
| -10 | 15.88mm | 5/8″ |
| -12 | 19.05mm | 3/4″ |
| -16 | 25.4mm | 1″ |
| -20 | 31.75mm | 1-1/4″ |
We have a large range of Speedflow fittings available, to suit all of your motorsport plumbing needs.
-
SpeedFlow Female Port – Male Y$51.04 -
SpeedFlow Male Y$68.95 – $107.36 -
SpeedFlow Female – Male Y$37.72 – $86.55 -
SpeedFlow Female – Male Step Y$62.72 – $105.58 -
SpeedFlow Female Tee Male On Run$57.59 – $73.19 -
SpeedFlow Female Swivel Tee$57.59 – $73.19 -
SpeedFlow Female Tee Male On Branch$57.59 – $73.19 -
SpeedFlow Tee Female On Run$34.49 – $86.24 -
SpeedFlow Tee Female On Branch$34.49 – $86.24 -
SpeedFlow Straight Adapter F-M M10 Port$22.42 -
SpeedFlow Straight Adapter F-M 1/4″ NPT Port$31.38 -
SpeedFlow Straight Adapter F-M 1/8″ NPT Port$22.42 – $63.50 -
SpeedFlow Straight Adapter M-M 1/8″ NPT Port$22.42 – $48.43 -
Speedflow BSPP to Straight Hose End$41.39 -
SpeedFlow 90 Degree Swivel Adapter F-M$34.49 – $87.27 -
SpeedFlow 45 Degree Swivel Adapter F-M$34.49 – $87.27 -
SpeedFlow 180 Degree Swivel Adapter F-F$34.49 – $74.37 -
SpeedFlow 90 Degree Swivel Adapter F-F$34.49 – $87.27 -
SpeedFlow 45 Degree Swivel Adapter F-F$34.49 – $87.27 -
SpeedFlow Straight Stepped Swivel Adapter F-F$24.13 – $43.11 -
SpeedFlow Straight Swivel Adapter F-F$20.68 – $68.97 -
SpeedFlow 30 Degree Hose End 100 Series$47.44 – $169.02 -
SpeedFlow 180 Degree Hose End 100 Series$60.36 – $169.02 -
SpeedFlow 150 Degree Hose End 100 Series$60.36 – $169.02 -
SpeedFlow 120 Degree Hose End 100 Series$60.36 – $169.02 -
Speedflow O-Ring Port to 90 Degree Hose End$81.14 – $101.44 -
SpeedFlow 90 Degree Stepped Hose End 100 Series$86.24 -
SpeedFlow 90 Degree Hose End 100 Series$47.44 – $169.02 -
SpeedFlow 60 Degree Hose End 100 Series$47.44 – $169.02 -
SpeedFlow 45 Degree Hose End 100 Series$47.44 – $169.02