Pre-cut PU film CGM sensor covers for Freestyle Libre sensors? Seriously?
You may find descriptions of the use of PU film adhesive products for CGM protection issues on the internet. We have mentioned this in other articles as well. Even if the adhesive is used properly, the poor breathability of the product can make the user's experience very unpleasant.
We have noticed that there is another type of pre-cut PU film adhesive product with a perforated hole in the middle of the tape used for the Libre sensor, which is a breakthrough in our theoretical understanding. Well, regardless of the breathability issue, the thickness of the PU film you see is less than 0.03mm without adhesive, and even with adhesive, it is within 0.05mm. The base layer of adhesive tape of the Libre sensor extends out of the product, about 2.5mm for Libre 2 and even smaller for Libre 3.
Therefore, even if your installation and use are correct, you have to use a plastic film as thin as a hair to cover the base layer adhesive tape of the Libre sensor, which is only 2.5mm in size. In other words, it is a joke to try to stick such a thin plastic film in such a small area to fix the entire sensor. You can try a small experiment yourself by using a regular plastic bag, attaching it to the edge of another plastic bag with as much adhesive as possible, and trying to pull these two pieces of plastic in different directions. If the result is that they are not pulled apart or deformed significantly, we would be very surprised.
Product research requires a combination of theory and practice and is a serious matter. Due to the breathability issue, Kovoq insists on not adopting the PU film solution but instead uses highly breathable Fabric material. However, even if you are convinced that PU film is your preference unless you only need a decorative effect, we strongly advise against using them on the Libre series products.