AlphaSense O2-A2 Oxygen Sensor

AlphaSense O2-A2 Oxygen Sensor
Regular price $70.00 USD

POs or wholesale quantity discounts click here

The AlphaSense O2-A2 oxygen sensor is a replacement sensor for hand-held gas detectors that use the O2-A2 sensor.

⭐⭐⭐⭐⭐ - Rated. Read our Reviews!

Verify the sensor you are replacing has AlphaSense O2-A2 printed on the side before ordering. Due to our low prices we cannot accept returns for the wrong sensor.


  • Electrochemical (EC) sensor designed to last for up to 2 years
  • Good pressure and temperature independence
  • Small, compact & maintenance free

Replacement Oxygen Sensor for

    • BW Technologies GasAlert MicroClip XT
    • BW Technologies GasAlert Max XT-II
    • BW Technologies GasAlert Micro 5 PID
    • BW Technologies GasAlert Quattro
    • BW Technologies GasAlert Extreme GAXT-DL-2
    • BW Technologies GasAlert Extreme GAXT-DL-B-2
    • BW Equivalent part no. SR-X10-C1
    • MSA Solaris Orion Altair 4,5 (not 4X or 5X)
    • Fieldpiece SOX3
    • CityTech 4OX-2
  • Measurement Range: 0.1-20.9% Oxygen
  • Output @ 20.9% Oxygen: 80-120 uA
  • Output @ 0% O2: < 2.5 uA
  • Response Time: < 15 sec. t90 (s) from 20.9% to 0%
  • Linearity: 0.6% O2 deviation @ 10%
  • Output drift: < 1% change @ 3 months
  • Operating life: > 24 months until 85% original Output of 20.9%


  • Dimensions (sensor): 17.4mm x 20.3mm
  • Current Consumption: 10ma peak, < 3mW average

Verify the sensor you are replacing has "AlphaSense O2-A2" printed on the side before ordering. Due to our low prices we cannot accept returns for the wrong sensor ordered.


Sensor Pin Sockets - Manufacturers do not recommend soldering to the pins. Pin sockets can be purchased from Andon distributors. Click here to search for your sensor's socket. Select the brand PDF, find your sensor, then search for the Andon part number for your sensor's socket.

Customer Reviews

Based on 36 reviews
Jorge Montes
Perfect fit

The sensor fits perfectly, no issues.

Daniel Howard
O2 Sensor

Always has the the product you need at the best price and timley shipping.

Lye Kiong
Service Engineer

Price increase horrible

We understand and agree. The supply chain issue has impacted all our products.

Srinivas Medidi
Oxygen level indicator

Will this sensor only sense oxygen or it will indicate the level of oxygen too? If not do you have such instruments?

We have all kinds of instruments and sensors to detect oxygen levels. Give us a call at (386) 872-7668 and a sales engineer. They will be glad to take your requirements and make a recommendation!

Donnie H
Alpha Sense 02-A2 Oxygen Sensor

Replacement for a bad 02 sensor for quattro gas alert. The Alpha Sense 02-A2 worked like it should. Back in business. Thanks Gaslab

"Swift response and shipment. The product is easy to setup and use. It is just what I was looking for."

- Shima Tomohiro

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