JB Industries M2-400 Low Side Gauge 4 in Blue 400 psi
4-inch low-side gauge reads 30 in Hg to 400 psi with ±1.00% accuracy for R-134A, R-22, R-404A and R-410A systems
- Product colorBlue, Glow-in-the-Dark
- Measures low-side pressure up to 400 psi for R-410A systems
- Glow-in-the-dark blue face reads clearly in dim spaces
- +/- 1.00 percent accuracy gives reliable refrigerant charge data
- 1/8 in connection fits standard manifold gauge sets directly
- 30 in Hg vacuum range supports full evacuation and recovery
HVAC Low-Side Gauge for Refrigerant Systems
The JB Industries M2-400 is a low-side pressure gauge designed for HVAC and automotive air-conditioning service. It suits technicians who need a replacement manifold gauge for existing sets. The blue colour coding identifies the low-pressure side at a glance. It is not for installers who require a high-side gauge or a complete manifold kit.
Pressure Range and Accuracy for Refrigerant
The gauge reads from 30 in Hg vacuum up to 400 psi with a stated accuracy of +/- 1.00 Percent. This range covers R-134A, R-22, R-404A and R-410A refrigerants. Selecting this gauge depends on matching those pressure limits and refrigerant types to the system under test. It will not suit applications that exceed 400 psi or use refrigerants outside the listed four.
Simple Threaded Connection with Common Pitfalls
Installation uses a 1/8 in connection thread that fits standard manifold blocks. The glow-in-the-dark dial face helps readability in dim engine bays. The most common error is cross-threading the fitting or over-tightening, which can damage the brass seat and cause leaks. Always verify the refrigerant type on the system label before connecting.
How it compares
Measured against everything we stock in Heating & Cooling Controllers, at today’s prices. Recalculated every night.
- Price $34.99
- Cheaper than about 58% of the 1,762 comparable items (median $45.99).
Specifications
| Product | |
|---|---|
| Brand name | JB INDUSTRIES |
| Product color | Blue, Glow-in-the-Dark |
Questions about this item
What does the 400 psi working-pressure rating tell me about real-world use?
The gauge reads from 30 in Hg vacuum up to 400 psi, so it covers the full low-side range of the listed refrigerants.
How does the 1/8 in connection affect compatibility?
The 1/8 in port matches standard manifold blocks, letting it thread directly into most replacement setups.
Will the 4 in diameter fit my existing manifold body?
The 4 in face is a common manifold gauge size and mounts in the standard panel cut-out used by many sets.
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