Drawing for illustration. Every gage is made to your size.
Made to order · APT · Dual or Single Master
Thru-Hole Air Plug Gage (APT)
Longest-wearing air plug for through bores: the nose guides the plug in and takes the wear.
- Sizes
- .059" to 8.260" (1.50 to 209.80 mm)
- Part number
APT-[jet+class]-[material]-[min/max]- Example
APT-12-C-.5000/.5005
Priced by size in the online configurator
Build & price online →- Build the part number and see the price in minutes
- Formal PDF quote emailed to you
- Dual Master or Single Master tooling
The thru-hole air plug (APT) is the everyday bore gage. Its jets sit back from the nose, so the nose guides the plug into the bore and takes the wear. That makes it the longest-lasting style. Use it whenever the bore goes all the way through.
Where the jets sit
Dimension A (nose to jet centerline) runs from about .190″ on the smallest plugs to just over 1″ on the largest. If you need to measure close to the bottom of a blind bore, choose the blind (APB) or super-blind (APS) style.
Dual Master or Single Master
Choose Dual Master tooling to set the gage with a minimum and maximum master and work with any two-master readout. Choose Single Master tooling to set on one master at nominal with a matched single-master readout such as the Air Gage Pro M5-L or M5-H. Not sure? Read single vs. dual master air gaging.
How to order
| Dual Master | Single Master | |
|---|---|---|
| Part number | Style – jet code + clearance class – material – min/max bore | Style – spec code – material – nominal master size |
| Jet codes | 1, 4 (large jet, above .323″) or 5 | 6, 7 or 8 |
| Body size | Minimum bore − clearance | Nominal master size − clearance |
| Masters needed | Two: minimum and maximum | One, at nominal |
Material: C chrome-plated or S hardened steel. Every probe has recessed jets, so body wear doesn't shift the reading, and an air relief groove along the gaging body so blind bores don't build up back-pressure.
What we need to quote
- Bore size and tolerance
- Bore depth, and whether it is through or blind
- Grooves, cross holes or chamfers near the measuring point
- Your readout make and model, or single vs. dual master
Handles, hose assemblies, extensions and readout fittings are on the accessories page. Full dimensions are in the air tooling catalog (PDF).
More air plug gages (air probes)
Blind-Hole Air Plug Gage (APB)
Jets close to the nose, for measuring near the bottom of a blind bore.
Sizes: .059" to 8.260" (1.50 to 209.80 mm)
Details & pricing →
Super-Blind Air Plug Gage (APS)
Deepest reach into a blind bore, with jets as close to the nose as they can go.
Sizes: .059" to 8.260" (1.50 to 209.80 mm)
Details & pricing →