My problem was to install these lamps on threaded two inch cast aluminum posts that housed their predecessors. I cut 3/4 inch plastic sheets to fit the base of the mounting brackets and drilled a slightly smaller than 2 inch hole in the center. The plastic base cut its own threads when turned on the post, providing a solid base. I used four stainless steel bolts rather than the provided screws to anchor the mounting base to the plastic base. Voila! The batteries charged in just a few hours, one even being in partial shade, and the illumination they provided was far above my expectations, maybe the equivalent of a 40 or 60 watt bulb. Time will tell about durability, but so far, just superiors. Kent

Good quality will last a long time