Tube Holder Dual Variable Flow, only Back Catalog number: 800073 Manufacturer: SENSIDYNE Availability: In the manufacturer's stock Price on request - + Recommended 800071 Tube Holder Housing End, 5/8", for 1/4" OD, Open E Price on request 800251 Tube Holder Kit, Dual Variable Manifold (Includes Price on request 811-9979-50 Sorbent Tube, XAD-7, 6X110, 100/50, 50/BX Price on request