Since it is a contact insecticide, permethrin will only work if there is effective direct contact between the insect and permethrin for a certain period of time. The smaller the insect, and the larger (relative) the contact surface between the insect and the active substance permethrin, the greater the effect of the clothing.
Permethrin is therefore excellent against ants, ticks, fleas, lice, mosquitoes, sand flies, in short small insects. Pewrmethrin is insufficiently present in Rovince clothing and is anchored so deeply in the fibres that it has no negative consequences for larger insects such as bees and horseflies. A bee is too big and heavy, and has too few contact points (legs) to be fatally hit. A tick, on the other hand, has a large contact surface, so that the effect is almost immediate/quasi instant.