Tube Holder Dual Variable Flow, only Back Catalog number: 800073 Manufacturer: SENSIDYNE Availability: In the manufacturer's stock Price on request - + Recommended 811-9979-50 Sorbent Tube, XAD-7, 6X110, 100/50, 50/BX Price on request 800072 Tube Holder Single Variable Flow, only Price on request 800071-10 Tube Holder Housing End, 5/8", for 1/4" OD, Open E Price on request