Ardinbir Photography 500W 5400K Macro Ring Light Lamp for Canon, Nikon, Panasonic, Sony, Leica, Olympus SLR/DSLR Cameras, Photo Studio and Portrait Tech-Global-Photo is the ONLY amazon seller authorized by Ardinbir Studio The Ring Light is applicable on all tripods with 1/4 thread. We do offer the replacement bulbs at the price of $35.95/each plus shipping charge. And the offer is to those who get the light from us only due to quantity limit