# Expanding Functionality with Modules

The Everything Presence Lite includes spare GPIO pins, allowing you to connect optional modules to enhance its capabilities.

Currently, we offer a [**Carbon Dioxide (CO₂) module**](https://shop.everythingsmart.io/products/everything-presence-one-lite-co2-add-on), with additional modules planned for future release.

Learn how to integrate the **CO₂ module** by following the setup instructions.

[Integrate the Carbon Dioxide (CO₂) Module](/doc/859aa38c-9204-4fee-b403-1028a706adb7)

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**Documents**

- [EP1 vs EPL: Which Sensor is Right for You?](https://docs.everythingsmart.io/s/products/doc/ep1-vs-epl-which-sensor-is-right-for-you-5B3RxiY3Kp)
- [Everything Presence One (EP1)](https://docs.everythingsmart.io/s/products/doc/everything-presence-one-ep1-3R178yZSUP)
- [Everything Presence Pro](https://docs.everythingsmart.io/s/products/doc/everything-presence-pro-nh3fIXmow9)
- [Everything Presence Lite (EPL)](https://docs.everythingsmart.io/s/products/doc/everything-presence-lite-epl-ZVnBzYzuX2)
- [Zone Configurator](https://docs.everythingsmart.io/s/products/doc/zone-configurator-93b9scGsa2)
- [Knowledge Base Articles](https://docs.everythingsmart.io/s/products/doc/knowledge-base-articles-KnRRmk4zvt)