Laser counters can now be purchased through our online store at the following link: Replacement Laser Counters – PurpleAir, Inc.. The laser counters for PA-II edition sensors come in a pair, while the PA-I-Indoor laser counter is sold individually. Make sure to select the appropriate version of laser counter for your device. All Plantower laser counters are pre-tested in PurpleAir test chambers before being sold.
It is possible that the laser counters in a PurpleAir device may need replacing over time. For more information on sensor maintenance, view this article: Sensor Maintenance.