1. Introduction
The CONTEC CMS50M Pulse Oximeter is a compact and easy-to-use device designed for measuring blood oxygen saturation (SpO2) and pulse rate (PR). It displays these values along with a bar graph and pulse strength waveform on a digital LED screen. This device is intended for sports and aviation use only and is not a medical device. It is lightweight and portable, making it convenient for on-the-go use.

Image: The CONTEC Pulse Oximeter in use, measuring blood oxygen and pulse rate.
2. Safety Information
WARNING: Pulse oximeters provide an estimated oxygen saturation level. Certain physical traits, including but not limited to darker skin pigmentation and melanin, may cause the oxygen level estimated value to appear higher than it actually is. Users are strongly recommended to establish a baseline value when healthy and at rest. It is recommended that users consult a licensed healthcare provider or professional on how to interpret user readings based on physical traits or characteristics.
Statements regarding dietary supplements have not been evaluated by the FDA and are not intended to diagnose, treat, cure, or prevent any disease or health condition.
3. Product Overview
3.1. Components Included
- CONTEC Pulse Oximeter x1
- User Manual x1
- Neck/Wrist Cord x1
- AAA Batteries x2 (may be included or required separately)
3.2. Device Features
The CMS50M Pulse Oximeter offers several key features for convenient and accurate measurements:
- Accurate & Fast Results: Measures SpO2 (blood oxygen saturation) and pulse rate quickly and accurately, displaying results on a digital LED screen with a bar graph.
- Portable & One-Click Use: Lightweight (approx. 50g with batteries) and designed for simple operation. Insert your finger into the chamber, and the result will be shown.
- Comfortable & Long Battery Life: Features a hypoallergenic medical-grade silicone fingertip clip that is soft and accommodates a wide range of finger sizes. Provides 20-30 hours of battery life and automatically powers off after 5 seconds of inactivity.

Image: Diagram illustrating key features such as SpO2, Heart Rate, Pulse Rate Bar Graph, One Key Measurement, Infrared Sensor, and Auto Switch-off.

Image: Labeled parts of the pulse oximeter including Power-on Key, Pulse Rate, SpO2 Saturation Level, Pulse Bar Graph, Low Battery Indicator, Battery Cover, and Lanyard Loop Hole.
4. Setup
4.1. Battery Installation
The CONTEC CMS50M Pulse Oximeter requires two AAA batteries for operation. Ensure correct polarity (+/-) when inserting the batteries.
- Open the battery cover located at the bottom of the device.
- Insert two AAA batteries, matching the positive (+) and negative (-) terminals as indicated inside the battery compartment.
- Close the battery cover securely.

Image: Illustration showing the correct insertion of AAA batteries into the pulse oximeter's battery compartment.
4.2. Initial Use & Protective Film
Before first use, you may notice a clear screen protector film on the display. This can be removed to improve visual clarity of the readings.
4.3. Instructional Video: How to Use
Video: An official CONTEC video demonstrating the steps to use the CMS50M pulse oximeter, including battery installation and taking a measurement.
5. Operating Instructions
To obtain accurate readings from your CONTEC CMS50M Pulse Oximeter, follow these steps:
- Prepare Your Finger: Ensure your finger is clean and free of nail polish. For best results, warm up your hands if they are cold.
- Open the Clip: Gently open the clip of the oximeter.
- Insert Finger: Place one of your fingers (preferably index or middle finger) into the rubber opening of the oximeter. Ensure your finger is fully inserted and resting flat on the sensor.
- Press Power Button: Press the power-on button once to activate the device.
- Remain Still: Keep your hand and finger still during the measurement process. Do not shake your finger.
- Read Results: After a few seconds, your SpO2 and PR values will be displayed on the screen. The device will automatically power off after 5 seconds of inactivity once the finger is removed.

Image: Step-by-step visual guide on how to use the pulse oximeter, from opening the clip and inserting the finger to pressing the button and viewing results.
6. Maintenance
Proper maintenance ensures the longevity and accuracy of your pulse oximeter.
- Cleaning: Use a soft cloth dampened with medical alcohol to wipe the surface of the device and the finger chamber before and after each use. Do not immerse the device in water or any cleaning solution.
- Storage: Store the oximeter in a cool, dry place, away from direct sunlight, high temperatures, and moisture. When not in use for extended periods, remove the batteries to prevent leakage.
- Handling: Handle the device with care. Avoid dropping it or subjecting it to strong impacts.
7. Troubleshooting
If you encounter issues with your CONTEC CMS50M Pulse Oximeter, refer to the following common troubleshooting tips:
- No Display/Device Not Turning On:
- Check if the batteries are installed correctly with the right polarity.
- Replace old or depleted batteries with new AAA batteries.
- Ensure the power button is pressed firmly.
- "Finger Out" Message or Inaccurate Readings:
- Ensure your finger is fully inserted into the oximeter chamber.
- Keep your hand and finger still during measurement. Movement can affect accuracy.
- Remove any nail polish or artificial nails from the finger being used.
- Ensure your finger is not too cold; warm your hands if necessary.
- Display is Dim:
- Replace the batteries.
- Remove the clear protective film from the screen if it's still present.
8. Specifications
| Specification | Value |
|---|---|
| Model Name | CMS50M |
| Product Dimensions | 2.24 x 1.34 x 1.22 inches |
| Item Weight | 3.21 ounces |
| Batteries Required | 2 AAA batteries |
| Measuring Range | SpO2: 0% to 100%; PR: 30bpm to 250bpm |
| Color | Blue |
| Manufacturer | CONTEC MEDICAL SYSTEMS |
| Date First Available | July 5, 2018 |
9. Warranty and Support
For warranty information or technical support, please refer to the contact details provided in the product packaging or visit the official CONTEC website. Keep your purchase receipt as proof of purchase for any warranty claims.
