Designed to "click" into place for easy installation and a secure fit. This allows the installer to "feel and hear" that a solid connection has been made, even when the connection is in a difficult-to-see location. Through a patented process, the terminals are attached to provide an extremely strong connection ensuring the cable and boot will not separate during removal and installation. Each wire in the set is pre-cut to exact length so the wire sets are ready to install right out of the box. The 7 and 8mm ignition wires are SAE J2031 Class E rated, the highest quality wire used in the industry. These wires can withstand temperatures from -40 Degree to 428 Degree F and pass tests covering everything from electrical properties to shrinkage to chemical resistance and accelerated life testing.