THE YELLOW JACKET 49117 A2L MANIFOLD GAUGE IS HOUSED IN A DURABLE RED STEEL CASE WITH A FRONT RECALIBRATOR SCREW. ITS LARGE 3-1/8″ GAUGES FEATURE HIGH-VISIBILITY COLORED TEMPERATURE SCALES, MAKING THEM EASY TO READ THROUGH THE FULL-VIEW POLYCARBONATE CRYSTAL. THE GAUGE’S FLUTTERLESS TECHNOLOGY, ALONG WITH THE BRASS SURGE PROTECTOR, MINIMIZES NEEDLE PULSATION, ENSURING ACCURATE PRESSURE READINGS FOR REFRIGERANTS LIKE R-32, R-454B, AND R-410A