The 54MZ-4 offers cutting edge technology with features such as Canon s E-TTL flash control, and high-speed synchronization (HSS). The 54MZ-4 is a special version of Metz s 54MZ-3 series flash that has been specifically designed for Canon series digital SLRs, and comes complete the SCA 3102 module for Canon. The 54MZ-4 has a built-in secondary flash that can be used as fill to produce wraparound lighting when the main flash, with its built-in tilt/swivel function, is bounced off a wall or ceiling. The main flash s Auto Zoom feature works with lenses in the 24-105mm range, producing a Guide Number of 177 (feet) at ISO 100 at maximum zoom setting and a Guide Number of 131 (feet) at ISO 100 at 50mm. This new flash unit retains the user-friendly operation control panel of the 54MZ-3 and offers nine different Automatic settings and well as a variable Manual mode, offering ratios down to 1/256th power. The 54MZ-4 is user-friendly with only two buttons, and a single thumb wheel controls the logically arranged menu system. The illuminated LCD panel is large and easy-to-read and only displays the pertinent mode information. Special features of the 54MZ-4 includes the display of focal length for the lens in use in the LCD screen. This display can be adjusted from feet to meters, or to various film/digital formats for standard 35mm, APS digital , 645, or 6x6. Other features are auto flash bracketing, auto shut-off, and lockable keypad eliminating accidental setting changes. Item Includes: Light reduction filter Carrying case Canon SCA3102 adapter