Tube Holder Kit, Dual Variable Manifold (Includes Back Catalog number: 800251 Manufacturer: SENSIDYNE Availability: In the manufacturer's stock Price on request - + Recommended 811-9963-50 Sorbent Tube, Microlite, 6X70, 200mg, 50/BX Price on request 106SC Carbon Monoxide 1-50 ppm Gas Detector Tube, pk/10 Price on request 811-9903-50 Charcoal Tube, Coconut Shell, Jumbo, 200/800mg, 10 Price on request