Abstract: A rung assembly has an overall length just short of the spacing between a pair of posts to permit it to be positioned therebetween, after which the assembly can be mounted on the posts by means of axial bolts at the ends of the assembly.The bolts are so housed by assembly end fittings that rotation of the fittings not only rotates the bolts but facilitates their outward axial movement as demanded by their engagement with the posts.The assembly is of adjustable length to facilitate mounting it on variously spaced posts.