FYY-03
Separate Continuous and Breathe controls, with a built-in 30 Wh battery.
Free U.S. shipping, including Alaska, Hawaii and Puerto Rico. Estimated delivery: 5–7 business days.
FYY-01
Continuous flow
Continuous outputUp to 1.8 L/min
Steady delivery through inhale and exhale.
Simple & lightweight
FYY-03
Breath-responsive
Peak inhale flowUp to 5 L/min
Continuous mode also available.
More flexible control
Peak inhale flow is not continuous output or a pulse dose. Both models deliver oxygen-enriched air. See full specifications for output details.
View full comparisonAny reason, opened or used. We pay return shipping.
Parts, repair or a new replacement. We cover the costs.
Power switches the device on and off. Continuous selects the continuous-flow settings; Breathe selects the breath-synchronized settings. Indicator lights show the selected mode and charging status.
Keep the device upright and its vents clear. Use the power supply specified for your device. Keep away from flames, smoking, oil and water. Switch off before cleaning the housing with a soft cloth. Do not share tubing or open the housing for repairs.
A closer look
Separate Power, Continuous and Breathe buttons. Find each control and connection at a glance.
USB-C
Switch the device on or off.
Select continuous-flow settings. Airflow continues during both inhalation and exhalation.
Select breath-synchronized settings. Delivery responds to inhalation and pauses during exhalation.
Connect the supplied oxygen tubing here.
Indicator lights show the selected mode and charging status.
Keep the lower side opening clear while the device is running.
Connect the specified USB power supply at the rear of the device.
Follow the instructions supplied with your device for button timing, settings and safe operation.
A change of scene
Compact, rechargeable and easy to bring along. From everyday walks to road trips and mountain trails.
Your portable setup, right by your side.
Oxygen-enriched air on the road, with a compact device beside you.
A shoulder-carried setup that leaves your hands free for the trail.
At a glance
Size, controls and output. A clear look at what each model offers.
| Flow mode | Continuous / breath-synchronized Breathe |
|---|---|
| Peak inhale flow / Breathe mode | Up to 5 L/min |
| Continuous flow / low | 1.2 ±0.2 L/min |
| Continuous flow / high | 1.8 ±0.2 L/min |
| Oxygen at outlet | 30% ±5% |
| Device weight | Approximately 1.9 lb (0.85 kg) |
| Device dimensions | Approximately 4.9 × 3.7 × 5.5 in (125 × 95 × 140 mm) |
| Battery | 30 Wh |
| Power input / rated power | 5 V / 2 A / 10 W |
Technical figures are nominal and may vary with settings and conditions. Outlet oxygen concentration is not the concentration inhaled.
MTEH oxygen enrichers
Questions about the MTEH FYY-01 and FYY-03 portable oxygen enrichers.
FYY-01 offers a fold-away handle and two continuous-flow settings, up to 1.8 L/min. Airflow continues during both inhalation and exhalation. FYY-03 has separate Continuous and Breathe controls. In breath-responsive Breathe mode, it delivers during inhalation and pauses during exhalation, with peak inhale flow up to 5 L/min. Continuous mode is also available. Peak inhale flow is not continuous output or a pulse dose. Both models deliver oxygen-enriched air; see each product's full specifications for output details.
Keep vents clear, use the specified power supply and keep the equipment away from flames, smoking, oil and water. Switch off before cleaning and follow the supplied instructions for tubing and accessories.
Standard shipping is free to all 50 states, Washington, DC and Puerto Rico. Estimated delivery is 5–7 business days from Seattle. All products include 30-day unconditional free returns, even if opened or used. We provide a prepaid return label and charge no restocking fee. Every product also has a 1-year warranty from delivery for faults during normal use. We can send parts or take back the product for repair or a new replacement, with necessary shipping covered by Seravni. See our shipping policy for delivery details.