These slippery strips of hard plastic make the insertion and use of a wedgeeasier in any situation. When you insert the Strip Savers prior to your wedgetool, you are going to prevent the weather stripping from rolling back anddamaging. The Strip Saver is thin enough that it will not create enoughpressure inside the door to cause any damage.There is a quickinstructional manual included, Instructional DVD available on request or anonline access code included with the kit that provides quick, expert trainingon the proper use of the included tools. Slippery surface Long enough to bypass weather stripping Durable hard plastic construction