The removable sieve columns for the GCE Zen-O portable concentrator contain the sieve filters that separate inert gases from room air and concentrate it into medical-grade oxygen. Replace them yearly to keep your Zen-O producing the correct oxygen concentration.
Designed specifically for the GCE Zen-O portable oxygen concentrator (the larger model). Not interchangeable with the GCE Zen-O Lite or other manufacturers' columns — if you have the Zen-O Lite, look for "GCE Zen-O Lite Column Pair."
Installation requires a screwdriver and a T10 Torx bit. If you don't already have one, you'll need to acquire it before changing the columns. T10 Torx bits are available at most hardware stores or as part of multi-bit screwdriver kits.
2 sieve columns — a complete set for replacing both at once. (Columns work in alternating cycles, so both should be replaced together to maintain proper oxygen output.) Tools not included — you'll need a T10 Torx bit screwdriver.
Replace the columns approximately once a year for best results. Heavy usage, dusty environments, or running at higher flow settings can shorten the interval.
What sieve columns do
Inside an oxygen concentrator, sieve columns are filled with a molecular-sieve material (typically zeolite) that adsorbs nitrogen from compressed room air. What passes through is the concentrated oxygen your machine delivers. Over time, the sieve material loses its capacity to bind nitrogen efficiently — which is why these columns need periodic replacement to maintain the proper oxygen concentration.
Call 1-800-775-0942 with your Zen-O details — we'll help confirm whether columns are the right replacement part.
About Main Clinic Supply
We're based in Rochester, Minnesota — home of the world-famous Mayo Clinic. We deliver free to all Mayo Clinic hospitals and local hotels. With FedEx's strong presence in Rochester, our family-owned business is able to ship late into the evening.
Inspired by Mayo Clinic's values, we prioritize helping people over making profits — embodying Dr. Mayo's 1910 mission statement: "The needs of the patient come first."

