Here is an image showing the pin diagram of this transistor.
Classification of hFE
The KSD1588-Y transistor can have a current gain of 100 to 200. The gain of the KSD1588 will be in the range from 40 to 200, for the KSD1588-O it will be in the range from 80 to 120, for the KSD1588-R it will be in the range from 40 to 80.
Complementary PNP transistor
The complementary PNP transistor to the KSD1588-Y is the KSB1097-Y.
Replacement and Equivalent for KSD1588-Y transistor