# Shimmer3 GSR+: Prerequisites

#### What is the Shimmer3 GSR+ Unit

The Shimmer3 GSR+ Unit is a wearable device that measures Galvanic Skin Response (GSR), also called Electrodermal Activity (EDA). It captures skin conductance changes due to sweat gland activity, reflecting emotional arousal and cognitive responses. 

The device also measures Photoplethysmography (PPG), the blood volume changes in the skin. The Cinematronic Biosignal Platform uses an algorithm to translate PPG signals into heart rate (HR) for extended physiological monitoring.

<figure><img src="/files/ki5aNZyGdtLYm1cD6vVE" alt=""><figcaption></figcaption></figure>

### Hardware Requirements

Cinematronic Biosignal Platform supports the Shimmer3 GSR+ Unit with firmware v1.12 and above.&#x20;

The following accessories are required:

* Finger electrodes (supplied with the unit)
* Electrodes straps, such as one of the types listed below:
  * Finger clamp (purchased separately).  Recommended for the Biosignal Platform .
  * Velcro straps (supplied with the unit). While they are well suitable for tests, they can be uncomfortable to wear.
  * Adhesive pads  (supplied with the unit). They tend to be the most accurate at registering data, but they are the most invasive to apply.
* A compatible Windows computer with a Bluetooth connection. See the software's [technical requirements](/getting-started/quickstart.md).&#x20;

The Shimmer2 GSR+ unit can be purchased on the supplier's [official webshop](https://shimmersensing.com/product/shimmer3-gsr-unit/).

### Software Requirements

The Shimmer3 GSR+ Unit does not require additional software to work, other than the software itself.


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