Yongnuo YN568EXN-USA i-TTL Speedlite Flash for Nikon, GN58, High-Speed Sync, US Warranty (Black) Acts as a wireless slave with full i-TTL for Nikon"s wireless remote flash triggering system High-speed sync up to 1/8000th of a second Automatic motorized zooming to match flash coverage area to the focal length of your lens Ultra-fast 3 second full-discharge recycle time with ordinary AA batteries Returns and service promptly performed in the USA for orders that are sold by and shipped from Amazon.com (must provide Amazon invoice copy for return authorization)