# Purple air zen- which is channel A and where are the slots to clean out

**URL:** <https://community.purpleair.com/t/purple-air-zen-which-is-channel-a-and-where-are-the-slots-to-clean-out/5817>\
**Category:** Sensors\
**Created:** [July 30, 2023, 11:48pm UTC](https://community.purpleair.com/t/purple-air-zen-which-is-channel-a-and-where-are-the-slots-to-clean-out/5817 "2023-07-30T23:48:55Z")\
**Posts on this page:** 1\
**Showing post:** 2

<div class="post-metadata">

**Author:** ![Ethan](https://sea2.discourse-cdn.com/flex020/user_avatar/community.purpleair.com/ethan/32/177_2.png) [@Ethan](https://community.purpleair.com/u/Ethan)\
**Post date:** [July 31, 2023, 6:00pm UTC](https://community.purpleair.com/t/purple-air-zen-which-is-channel-a-and-where-are-the-slots-to-clean-out/5817/2 "2023-07-31T18:00:52Z")

</div>

Hi @Eric, the process for cleaning the laser counters in the same for every device. The “B” channel is the laser counter closest to the USB port. We will update our documentation to reflect this.

More information is available in our [sensor maintenance article](https://community.purpleair.com/t/sensor-maintenance/1531).

---

_[View the full topic](https://community.purpleair.com/t/purple-air-zen-which-is-channel-a-and-where-are-the-slots-to-clean-out/5817)._