The red spray safety ring was developed to prevent unintentional spraying (e.g. by children or vandalism on the sales shelf).
This small red ring is located under the protective cap and under the spray head. When you remove the spray head, the ring can be lifted very easily with a pointed object, e.g. a screwdriver, and pulled out. Please do not use force when doing this, as this could damage the can and the contents of the can could come out. Important: the spray retaining ring can be reinserted later.