1.sight glass-extended tube with nut, for refrigeration and air conditioning 2.excellent quality and service sight glass-extended tube, for refrigeration and air conditioningHH No.Male x Female201SG02MF1/4" x 1/4"201SG03MF3/8" x 3/8"201SG04MF1/2" x 1/2"201SG05MF5/8" x 5/8"201SG06MF3/4" x 3/4"Primary Competitive Advantages:Quality Approvals Price Service Certificates:ISO9001: 2008 ISO14001: 2004 ...