Replacement Bottle of Calibration Gas from Portagas
Size: 100 Liter
Concentration: 100 PPM Carbon Monoxide (CO) with a Balance of Nitrogen (Please let us know if you need a different concentration at check out)
Shelf Life: 48 Months
These are the Special “PortaGreen” Refillable Cylinders. It even includes a return shipping label.
PortaGreen provides a hassle free cylinder return program designed to reduce HAZMAT costs and your carbon footprint.
Here is a link to learn more. http://www.portagas.com/products/portagreen/
Gas Clip Technologies