Yongnuo YN-510EX is a versatile and powerful flash unit that offers a wide range of features and capabilities for photographers of all levels. With its high guide number of 58 at ISO 100 and 105mm, the YN-510EX provides ample illumination for even the most challenging lighting conditions. The flash head can be tilted up to 90 degrees and rotated left and right for bounce flash photography, giving you greater control over the direction of light. The YN-510EX also features a built-in zoom function that allows you to adjust the coverage of the flash from 24mm to 105mm, ensuring that you have the perfect amount of light for your subject and composition.