From the VOLO website...
Unlike any other LED, the VOLO LEDs were specifically designed for multirotors. They offer a bright, tight cluster of LEDs and are available in a range of colours. They are so small you can mount them almost anywhere on your frame, and they attach easily with the incredibly strong supplied die cut 3M VHB double sided tape. VOLO was the first company to produce this concept and nothing rivals our quality and performance.