"KIT CONTAINS: (1) BRASS DETECTOR TUBE BODY, (1) BLUE EXTENSION HOSE, (3) ACID DETECTOR TUBES, (3) MOISTURE DETECTOR TUBES, (3) EASY OIL TEST DETECTOR TUBE, & (1) 1/4 X 1/4 BRASS MALE UNION. MEASUREING ACID AND MOISTURE LEVELS IN BOTH THE COMPRESSOR OIL AND ANY REFRIGERANT GAS."