BMW rotor hold down screws tend to rust and corrode in a sort period of time and become difficult to remove.
ECS now has stainless steel rotor hold down screws to protect from this corrosion.
Sometimes it's the little things that count, like not having to drill out a little screw to change your rotors.
ECS Tuning: BMW Rotor Hold Down Screw Corrosion Test - YouTube
Click HERE to order and for more information