Prevent Scratches with Door Sill PPF. In this video, we show how to protect the door sill (threshold) of your car using clear Paint Protection Film (PPF) — the perfect way to avoid scratches, scuffs, and damage from shoes when getting in and out of the vehicle.To make the process safe, we use a green protective line tape — placed between the paint and the cutting area. This tape doesn’t cut the film, but it creates a safe distance for the blade, helping you trim the PPF without risking any damag