The SD-8A is designed for use with the SB-800 and SB-27 to shorten flash recycling time and enhance flash capacity. It accepts six 1.5V LR6 (AA-size alkaline), 1.2V KR-AA (R6/AA-size NiCd), 1.5V FR6 (AA-size lithium) or 1.2V R6/AA-size Ni-MH batteries.