We start with the finest 6061-T6 billet aluminum, CNC machined it to perfection The assembly is then mated with a 2" tall, USCG approved, high flow, multi-layered stainless steel screened element The top and bottom sections rest solidly on unique standoffs which will not allow the element to be crushed as can happen with common filter elements. Length is 21-1/2, and width is 10-1/2