This module uses a ultra-bright infrared (IR) LED and a phototransistor to detect the pulse in your finger. The red LED then flashes in time with your pulse.

Working principle: Shine the bright LED onto one side of your finger while the phototransistor on the other side of your finger picks up the amount of transmitted light. The resistance of the phototransistor will vary slightly as the blood pulses through your finger.

Features:
Great for electronic and electrical experiments.
Enables interaction with light-related works.
It is very suitable for working for Arduino to build a circuit prototype.
Excellent board and great quality!
Suitable for all kinds of scientific experiment research for Arduino.

Specifications:
Brand: Keyestudio
Model: Pulse Rate Monitor
Material・FR4
Color: Black + Yellow
Working Voltage・3.3-5V
Application: For Arduino study and application
Type: Digital
Working Voltage:5V
PH2.54 socket White LED light module.
Item Size: 3.3 * 2.5 * 0.8cm / 1.3 * 1.0 * 0.3in
Package Size: 5 * 3.5 * 1cm / 2.0 * 1.4 * 0.4in
Package Weight: Approx. 5g / 0.18oz

Package List:
1 * Pulse Rate Test Module