The Di 866 is specifically designed for use with digital SLR cameras & comes with many worlds first features. This new flash unit is simple to use & can also be fired wirelessly where it can be used as a master or receiver. Nissin released the Sony fit version of this popular flashgun in March 2011. With a guide number of 60m the Di 866 features Nissins original My TTL user adjustable TTL light output level & is firmware upgradable thanks to an onboard USB (Universal Serial Bus) port. The gun also features high speed synchronisation & a fill in sub-flash (12m 100 ISO), which is activated while the main flash is bounced & also has a built-in wide angle diffuser & catch-light reflector. The flash gun comes with an auto-rotate colour display that stays upright whichever way the unit is tilted. The display utilises user-friendly icons to enable ease of operation.