The JB Industries M2-460 2.5" Compound Gauge is a precise tool for measuring refrigerant levels in HVAC and refrigeration systems. Made of durable alloy steel, this non-illuminating gauge is designed for use with R-22, R-404A, and R-410A refrigerants. With a compact size of 2-1/2" and a weight of 0.35 pounds, this blue-colored gauge is easy to handle and store. This model from JB Industries is a reliable and essential tool for professionals in the HVAC and refrigeration industry.