General Tool & Instrusments' Digital Refrigerant Leak Detector, No. RLD400, detects all commercially available HFC, HFO, HC, HCFC and CFC refrigerant gases, including many new ozone layer-friendly blends, such as R-22 and R-1234yf. The tool can help technicians prevent AC system components damage, repeated system recharges and inefficient cooling operation. It draws in samples via a true mechanical pump, which increases sensitivity. Other features—like three user-selectable sensitivity levels, triple-redundant leak indication, automatic calibration and reset, leak test vial and durable construction—boost the instrument's effectiveness in challenging environments, according to the company.