Molekule Air Pro, Air Mini and Mini+ all utilize a multi-layer PECO-Filter that combines and integrates the Pre-Filter and PECO together.
In this integrated filter, there is a Pre-Filter layer and a PECO-Filter layer. Pollutants are still filtered by a Pre-Filter layer first and then the destruction happens on the PECO-Filter layer.
The Pre-Filter layers in Mini and Pro are larger than the single pre-filter in Air so they only need to be changed every 6 months.