The Pulse indicator LED is covered by semi-transparent sticker by default. The sticker covers the LED hole agains dust and particullary to highly unwanted water or ice dropplets.
The sticker at same time reduce visibility of the LED. Althought the device is designed for maximal visibility of indicator LED possible it should be insuficcient in some daylight conditions. For that case we suggest carefully dismount the lid from the TFRPM01 and punch the sticker from outside to in the the plastic case. This dramatically increase the LED visibility.
Please note that change is considered as product modification and therefore the TFRPM01 could not be returned. You can always use the TFRPM01 case model and print the case without stickers, therefore save the original ones from damage.