Roof hooks with 3 height adjustment in the base plate (40.47.54 mm) and 30 mm adjustability on the bracket. Overall height adjustability: 120.5mm - 165.1mm For narrow rafters from 36mm With pre-assembled Climber 36/50 and cylinder head screw. For attaching the K2 SingleRail and CrossRail mounting rail. Material: Aluminum EN AW-6063 T66; A2 stainless steel.