Brighten your subject or an entire room with the YN560Li Lithium Speedlite from Yongnuo. This flash, which has a guide number of 58' at ISO 100 and 105mm, can fire at full power with a recycle time of just two seconds. It can also be used as a master or slave flash at a range of up to 328'. The flash can be fired at full power up to 500 times on one set of 18650 batteries.