Descriptions: Supports ETTL Flas: Supports FEC, FEB, Front and Rear-curtain sync, FE lock, Modeling Light, support for Canon camera menu accessible.  Double-Tube Macro Flash: Supports flash ratio adjustment, there are 8 levels (1/128-1/1) for the intensity adjustment for the flash control, total 22 levels fine tuning; the tube A and tube B can flash individually, the flash index is wider and more practical.  The Flash Tube Installation: Install the tube on the top of the flash;  Install the adapter ring on the front of the lens,then install the flash tube on the adapter ring.  The Flash Coverage: Vertical angle: Upwards,downwards 90 degrees;  Horizontal angle: inwards 60 degrees,outwards 30 degrees;  The rotate degree of the adapter ring: upwards 50 degrees, downwards 30 degrees;  The flash tube can be installed on the tripod for use.  Ultra-fast Charging Recycle System: It just take 3 seconds at full output. Even if not using the brand new batteries, it just takes 4~5 seconds to recycle.  C.Fn Setting Custom Function: You can customize the function as needed through the custom function.  LED Focus Assist Light: The LED focus assist light is divided into low light and highlight mode,achieve rapid precise focus.  Equipped with PC Sync Interface: The YN24EX is equipped with standard PC synchronous interface which allows you convenient to use synchronous flash by using PC synchronous line.  Supports the Lens of Multiple Filter Size: Supports the lens of the following filter size: 52mm, 58mm, 62mm, 67mm.  Low Battery Remind Function: When the battery power is insufficient,the red light will blink which remind you to replace the battery timely.  Sound prompt system: When the sound prompt system is enabled, different sound modes will prompt different working conditions of the speedlite so as to allow you to focus on shooting process (Note: the sound can be turned off).  Equipped with the External Power Socket: YN-24EX is provided with external power socket to meet your higher demand of recycling time and no longer missing the wonderful moments.  Automatic Settings Saving: YN-24EX can automatically save your current operating settings to convenient your next use.  Compaible Cameras: For Canon 1Dx, 1Ds series, 1D series, 5DIII, 5DII, 7DII 5D, 6D, 7D, 80D, 70D, 60D, 50D, 40D, 30D, 20D, 750D 700D, 650D/T4i, 600D/T3i, 550D/T2i, 500D/T1i, 450D/Xsi, 400D/Xti, 350D, 100D, 1100D, 1000D, 1200D.  Specifications: Model: YN24EX;  Circuit Design: Insulated Gate Bipolar Transistor (IGBT);  Type: Automatic macro flash for close-up photography;  Flash Ratio Control: Two flash heads: 24/79, Single flash head: 26/85 (ISO 100 105mm );  Flash Coverage: Vertical Angle: Upwards, downwards 90 degrees;  Horizontal Angle: Inwards 60 degrees, outwards 30 degrees;  The rotate degree of the adapter ring: Upwards 50 degrees, downwards 30 degrees;  Guide No.