The main advantage of the diamond files are that the texture is random, rather like emery paper or a buffing stick. They dont have teeth like a larger file. This means that the diamond files will work in any direction, either side to side or push and pull. Unlike a traditional file with only cuts on the push stoke, these will cut on both hence there is no wasted motion when you pull it back.This makes them very useful for small areas, where you cant get a full stroke with a regular needle file. Each shape is invaluable for a particular job.Round is great for inside jump ringsFlat is great for running in between the joint of a ring prior to soldering.Half round is perfect for inside rings, after soldering.Triangular has a very sharp point and is great for getting into tight areas.The square for tiny joints where two surfaces meet at 90 degrees.All great, I use these all the time.