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Small fingertip pulse oximeter with OLED screen and lanyard

HOLFENRY Pulse Oximeter JKS50BL Fingertip SpO2/HR/PI OLED Graph

SKU CH-3RF9-P237S

Measures SpO₂, heart rate and perfusion index with a real-time OLED graph in 5–8 seconds

  • TypeFace Mask
  • Size7.5 in x 0.8 in x 9.25 in
  • ColorWhite/Clear
  • GenderUnisex
  • AgeAdult
  • Item Count3
  • Measures SpO₂, heart rate and perfusion index simultaneously
  • Real-time OLED graph shows pulse waveform as it happens
  • Readings ready in 5–8 seconds with ±2 % accuracy
  • Auto power-off after 8 seconds of inactivity extends battery life
  • Includes lanyard and two AAA batteries for immediate use

Purpose and audience

The HOLFENRY JKS50BL fingertip pulse oximeter measures blood oxygen saturation, heart rate and perfusion index for users aged 12 and above. It is intended for sports, aviation and general wellness tracking rather than clinical diagnosis.

Measurement limits

Readings update in real time and the stated accuracy is ±2% for SpO2. Bright ambient light can interfere with the infrared sensor so indoor use is recommended. The device shows a dynamic heart-rate graph on its OLED screen but provides no data storage or wireless transfer.

Installation and common issues

Insert the two included AAA batteries, clip the unit onto a finger and press the single button to start. It powers off automatically after eight seconds of inactivity. Cold fingers, nail polish or excessive movement during the 5–8 second measurement window can produce unreliable results.

Highlights

  • Measures SpO₂, heart rate and perfusion index simultaneously
  • Real-time OLED graph shows pulse waveform as it happens
  • Readings ready in 5–8 seconds with ±2 % accuracy
  • Auto power-off after 8 seconds of inactivity extends battery life
  • Includes lanyard and two AAA batteries for immediate use

Specifications

BrandPETER PAUPER PRESS
ModelWEGOVY 1.7 MG/0.75 ML PEN INJ
Part Number5
TypeFace Mask
Size7.5 in x 0.8 in x 9.25 in
ColorWhite/Clear
GenderUnisex
AgeAdult
Item Count3
FeaturesAnti-Aging, Red LED Light Therapy, LED Light Mask, Treat Blemishes, Calm Redness

Questions about this item

Which model suits sports and aviation monitoring for users aged 12 and above?

The JKS50BL fingertip oximeter is designed for sports and aviation use by teenagers, adults and the elderly from 12 years old.

What do the SpO₂ and PR readings represent in everyday use?

SpO₂ shows blood oxygen saturation with a normal range of 94-100%, while PR displays resting heart rate between 60-100 beats per minute.

How does the infrared sensor limit measurement conditions?

Because the device uses infrared detection, bright ambient light can reduce accuracy so indoor use is recommended.

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