Tube Holder O-Ring Kit Back Catalog number: 800238 Manufacturer: SENSIDYNE Availability: In the manufacturer's stock Price on request - + Recommended 800075 Tube Holder Quad Variable Flow, only Price on request 200187 Tube Holder Adapter, 3/16" to 1/4" Ends Price on request 124SA Sensidyne Gas Detector Tubes, Toluene (10-500 ppm), pk/10 Price on request