Types of Concertina Razor Wire – Now, concertina wire can be flat or coiled type and then again it could have single or double coils. Double concertina wires are made with two pieces of stainless steel razor wire or with zinc coated razor wire; which are bound together for more strength. Single Coil Razor Wire Concertina – This is basically a hot dipped galvanized steel plate with strip processed razor wire coils which are extended in spiral type. Clips are generally not needed for this type. Large Coils Crossed – Crossed spirals of razor wire are clipped together. Y Post Supported Concertina Wire Fences – Concertina wires are mounted on top of a Y fence post. Electrified Concertina Wire – These are also called electrified safety fences. These are used along with electric power for enhanced security. A copper wire is placed inside the core wire of the razor blade.