The Rohn R-AS455G single accessory shelf is designed to bolt to all three side rails of any standard Rohn model 45G or 55G series tower section to accommodate the mounting of beacon lights, antenna rotors, and similar top-mounted attachments anywhere along the section length or at the section top. It comes complete with three (3) attachment U bolts and is pre-drilled to accommodate many of today's most popular antenna rotors. Field drilling may be necessary for your particular model.