The metal plate (16) has at least one bore (12) for holding a threaded bolt (14). The bore has a first inner diameter larger than the main diameter and several, preferably three, noses (34) which extend radially inwards to form a second inner diameter which is larger than the secondary thread diameter and smaller than the main thread diameter. At least a first nose has a point extending from the first inner diameter to the second inner diameter. It has sides formed in part by adjoining curve sections. A gap is formed circumferentially between at least two of the noses and is sufficiently large to allow the threaded bolt to be screwed in and out of the bore. A second metal plate can be connected to the first metal plate. The second plate has a bore the size of the first inner diameter.
