Apex RB-1004-49 Universal Side Rail Mounted Crossbars Adds cross bars to existing vehicle roof side rails extending cargo transport ability and a great solution for creating a roof cargo basket or bag mounting area Requires 36-48 inch distance between side rails maximum 180 lb capacity Adjustable and rubber coated clamps fit side rails 1"w to 6.75"W x 2"h Key-locking mechanism controls knob movement to deter theft (4 locks total) Remove from vehicle when not in use