Abstract: A clamp comprises: a first jaw (2) and a second jaw (3) having opposing contact surfaces (8, 9) which are relatively substantially linearly displaceable between a position of minimum separation and a position of maximum separation, wherein in use the opposing contact surfaces (8, 9) contact the lower surface and upper surface respectively of a structural element, wherein the first jaw (2) incorporates a first aperture remote from the contact surface and adapted to receive a suspension element or fastener; one or more means for guiding the first jaw (2) and the second jaw (3) during relative substantially linear displacement such as to substantially prevent relative non-linear displacement of the opposing contact surfaces (8, 9); and means for delimiting the substantially linear displacement of the opposing contact surfaces (8, 9) of the first jaw (2) and second jaw (3) to the position of maximum separation.