Milton Tire Inflator Gauge S-506 — Dual-Head 15" Hose, 10–160 PSI, Replaceable Cartridges

The Milton S-506 is a heavy-duty dual-head tire inflator gauge with a 15" hose that measures 10–160 PSI and offers replaceable gauge and valve cartridges.

Built by the company that introduced this style to the market, the Milton S-506 combines a rugged metal inflator body with a magnified dial for easy reading and a dual-head chuck to reach awkward valve stems. It’s designed for repeated workshop or roadside use and fits a wide range of wheeled equipment, from passenger cars to ATVs and lawn tractors. The 1/4" NPT air inlet and ⅜-24 threading make it compatible with most compressors and fittings used in garages and service bays.

How accurate is the Milton S-506 and what scale does it use?

The Milton S-506 is performance-tested and calibrated to give reliable pressure readings within its range. The gauge reads in pounds per square inch (PSI) from 10 to 160 in 2-psi increments; kilopascal (kPa) ranges are available by special order.

• PSI range: 10–160
• PSI increments: 2 lb.
• Optional kPa range: 80–840 (20 kPa increments) by special order
• Magnifying lens improves dial legibility

What makes the dual head chuck useful for tire work?

The dual head design gives two access angles so you can reach valve stems on tight or recessed wheels without forcing the tool into uncomfortable positions. One head is straight and the other is angled allowing you to seal the valve quickly while keeping the hose clear of spokes or lug nuts.

• Two heads: straight and angled for accessibility
• Full-swivel chuck to align with valve stems
• 15" hose to reduce strain and reach across wheel wells
• Self-sealing action works once tire has some pressure

Can the Milton S-506 be maintained or repaired?

Yes — Milton designed the S-506 for long life with replaceable cartridges so wear parts don’t mean replacing the whole tool. Both the gauge cartridge and the valve cartridge can be swapped out to restore performance after heavy use.

• Replaceable gauge cartridge extends service life
• Replaceable valve cartridge for reliable sealing
• Heavy-duty construction resists shop and field wear
• Standard 1/4" NPT inlet for easy connections

How do I use the dual head chuck if air leaks from the unused side?

If you notice air escaping from the off-side when connecting to a Schrader valve, remove the chuck, point the straight outlet upward, squeeze the trigger to let air flow, then place the chuck onto the valve while air is flowing. This allows the sealing valve to drop into place and form a proper seal.

• Not suitable for inflating a completely flat tire from zero pressure
• Release trigger and reposition while air flows to seat the seal
• Use only after confirming compatible fittings and safe pressure source

Who is this for: The Milton S-506 is aimed at professionals and serious DIYers who need a durable, serviceable inflator for regular use. It’s appropriate for automotive shops, tire technicians, motorsport crews, and homeowners who maintain multiple vehicles or equipment. If you value accuracy, accessibility to tricky valve stems, and the ability to replace wear parts instead of replacing the entire tool, this gauge is a practical long-term choice.