A method of providing extra air to the exhaust stream of an internal combustion engine. In various embodiments, the system can include a specially-configured coupler that enables PLC communications signals to pass to all power lines but without interfering with the operation of the electric power meters. Additionally, the fiber optic cables and assemblies have a relatively large slack storage capacity for excess length. A thickness direction dimension being the distance from the second principal surface to a portion of the sub-package most distant from the second principal surface, is not more than a thickness direction dimension being the distance from the second principal surface to an edge of the first bonding material at the second principal surface. Consequently the teeth of the blade travel in a loop pattern that crosses itself. The first side has at least one of a surface material or a texture relating to the sport, and the second side includes an indentation or \u201cworry groove.