We are often asked the difference between these two similar humidity sensors from Sensirion.AG, SHT41-AD1P-R2 and SHT41-AD1F-R2.
We reached out to the supplier on this and they responded with the following:
The SHT41-AD1P has a plastic protective cover that must be removed after assembly. This cover is designed to prevent conformal coatings from entering into the sensor while the SHT41-AD1F has a permanently attached PTFE membrane that is designed to keep dust and debris out of the sensor during operation.