Contec CMS-50D Fingertip Pulse Oximeter at best price.
Checkme Lite Handheld Oximeter with ECG – Wellue
Amazon.com: CMI Health Rechargeable Pulse Oximeter - Adult Finger Sensor for Continuous Monitoring & Spot-Checking - Adjustable Alarm for Pulse Rate and SpO2 Levels - Carry Case, AC Adapter Included : Health
Pulse Oximeters for Blood Oxygen Saturation | Walgreens
Easy@Home Fingertip Pulse Oximeter (Not for Medical Use) - SpO2 Blood