To simplify and facilitate installation of an antenna at the site.

This fitting 10 forms screwing holes 11b and 11c in a tongue- piece part 11a provided on a pole-side fitting 11, a pivotally-attaching hole 12b is formed in a tongue-piece part 12a provided in an antenna-side fitting 12, and at the same time, a movable long hole 12c in a circular-arc shape is formed along a circle which has an equivalent radius to the space between the screwing holes 11b and 11c centering the pivotally-attaching hole 12b. The both tongue-piece parts 11a and 12a are superposed to match the screwing hole 11b with the pivotally-attaching hole 12b and fixing them by a bolt nut 13, and also to match the screwing hole 11c with the movable long hole 12c and fixing by a bolt nut 14.