Box within a box.
When packing fragile items, wrap them in bubble wrap and put them in a smaller box. Then wrap the smaller size box with bubble wrap and put it in a larger box. It's much easier to immobilize / cushion the smaller box (which is larger and weighs the same as the object within it) than to do the same to just the item. Also, while the larger box may get damaged in shipping, it's much more likely for the smaller box and item to survive unscathed.
Ted