The invention relates to a device in a load carrier for vehicles, which is intended for roof mounting, said load carrier having support members (3) which are adapted to rest against the upper side of the vehicle roof (1) close to the edge thereof, a gripping member (9) gripping the edge portion of the vehicle roof, actuators which are actuatable by means of a lever (4) and adapted to clamp round the roof edge, and a handle (14) in connection with the lever (4) for operating the same. According to the invention, the lever (4) and the handle (14) are interconnected by means of a pivot (13) which in the active state of the device, i.e. in its clamping position, is positioned in the area of the upper part of the support member, while the lever at its other end portion is non-positively connected to said actuators in the area of the lower part of the support member (3), the handle and the lever forming a toggle joint system, which is foldable from the clamping position with a folded knee located in the upper part of the support member by pivoting the lever outwards to the release position of the device while straightening said knee.