collar the vacuum assists in increasing the effectiveness of the apparatus and makes it possible to use the apparatus at various altitudes without loss of effectiveness next a jacket 13 is placed on said hoop in one embodiment said jacket is a 1 2 profile semi circular cross sectioned piece of 6061t4 aluminum aluminum is used for strength and durability its use is ideal for use on large heavy vehicles or machinery in the case of small passenger vehicles or small machinery the aluminum jacket can be replaced with an abs plastic jacket or other material adapted to achieve additional sound insulation and noise reduction said jacket is 0 065 inches thick and is formed in a hoop with its concave face at the interior of said hoop 2 said jacket is sized in length to fit said hoop and not overlap said hoop collar for different applications said jacket will be different lengths to form a continuous outer perimeter when brought into contact with both ends of said hoop collar thus the outside perimeter of said hoop from collar edge to collar edge has a uniform outside diameter when said jacket is in place said jacketed hoop is a balancing hoop assembly 19 due to the weight and dimensions of said hoop collar a jacket is desirable to.