Robinair TIFZX-15 Replacement Filter Element for TIFZX-1 Leak Detector - 5 Piece Robinair Refrigerant Detector Replacement Filters Designed for use on Robinair TIFZX Heated Pentode Refrigerant Detectors Genuine Robinair replacement components with exact OE performance Rugged plastic housing Pack of 5 TIF Instruments TIFZX-15 Replacement Filter Elements For TIFZX-1 Leak Detector - 5 each TIF Instruments Replacement Filter Elements for TIFZX-1 Leak Detector. It comes in a package of 5 each. Replacement filter elements For TIFZX-1 Leak Detector Package of 5 each