Silver AussieSpeed FORD CROSSFLOW HEAD Falcon Cortina Aluminum rocker cover. AussieSpeed fully baffled breathers that aftermarket or factory PCV valve & after market push in breather cap. The cover is 14mm taller so no problem clearing roller rockers.When fitting the cover 1/4 unc or 1/4 whitworth fasteners will be required.The length required excluding the head or the thread for the nut is around 86mm.if using counter sunk allen key fasteners the total length including the head length is 86mm .