Knee pads are built to provide comfort. They stay in place no matter what types of trousers or pants you wear. But how you wear them, it matters. If you wear them over pants, they will hold your pants tightly. As a result, you may feel a bit uncomfortable. On the contrary, if you wear knee pads under pants or trousers, you can feel the ultimate comfort and do your job comfortably. But when it is about tactical knee pads, it is best to wear them over pants.