.Ideal for close up work of all kinds as well as creative portraiture, the MK-14EXT TTL Macro Ring Flash for Nikon from Meike is specifically designed for Nikon i-TTL. With a working range of 8" to 16.4', the ring light features a dual flash tube design with the ability to fire both tubes simultaneously, one at a time, or at separate power levels in 1/2-stop increments to create a light-to-dark ratio. Recycling time is 0.1 to five seconds with four separately-purchased AA batteries that give you 100 to 800 flashes. An optional external battery pack is available to increase flash capacity. Meike has made it possible to use a wide variety of lenses with the inclusion of 52, 55, 58, 62, 67, 72, and 77mm adapter rings. A leather carrying case is provided for storage and transport.