Milton S-921 Pencil Tire Pressure Gauge
- Up to 50 PSI or 350 kPa on one scale
- 4 side nylon indicator bar in a plated brass body
- Single chuck head for passenger car valves
- Built-in deflator valve for bleeding pressure
Last refreshed Sep 11, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A simple pencil gauge for checking passenger car tires, with dual unit markings and a built-in deflator. The scale stops at passenger car pressures, so tires inflated past its top reading need another gauge.
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ASIN: B0002SQYTGModel: S-921Category: Tire Gauges
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Overview
A nylon indicator bar slides out of a plated brass barrel when the chuck is pressed onto a tire valve, and the pressure is read where the bar stops. Milton's pencil gauge also has a deflator valve built in, so pressure can be let out and checked with one tool.
Milton limits the design to a brass barrel and a sliding bar, so there is no dial or screen to fail. The scale covers passenger car pressures only, and Milton lists no warranty for it.
Who it's for
Drivers who want a small check for a car's tires before a trip will find enough here. Owners of high pressure tires, or anyone wanting a lit digital readout, should skip it.
Pros and cons
- Reads both PSI and kPa
- Built-in deflator valve
- Plated brass body
- Four sided indicator bar
- Scale tops out at passenger car pressures
- Sold with no warranty
- Single chuck head only
- Listing material field says plastic
Performance notes
Tire pressure pushes the nylon bar out of the barrel, so the reading depends on pressing the chuck squarely onto the valve for a full seal. Milton advises checking tires cold, before driving warms them and raises the reading.
Specifications
| Brand | Milton |
|---|---|
| Model | S-921 |
| Dimensions & fit | |
| Item weight | 0.05 pounds |
| Item dimensions | 8.1 × 1.2 × 1.1 inches |
| Capacity & performance | |
| Pressure range | Up to 50 PSI / 350 kPa |
| Construction & materials | |
| Material Type | Plated Brass |
| Included components | |
| Included Components | 1 pencil tire pressure gauge |
| Other details | |
| Chuck type | Single chuck head |
| Deflator | Built-in deflator valve |
| Indicator | 4 side nylon bar |
Frequently asked questions
How big is the Milton S-921 pencil gauge?
The listing gives 8.1 x 1.2 x 1.1 inches and a weight of 22.68 g, small enough for a glovebox or door pocket.
Can the Milton S-921 check truck or RV tires?
Only tires run within its passenger car scale. It is built for passenger cars and reads to the top of its PSI and kPa range, not beyond.
Does the Milton S-921 let air out?
Yes. The title lists a built-in deflator valve for bleeding off pressure.
When should I check tire pressure with the Milton S-921?
Milton says to always check tire pressure when the tires are cold.