HSC95-AB Power Control-CK Four-slot expansion backplane mounting unit for BA11 KU/KV - boxes or in PDP 11/84, 11/44, and 11/24 HSC95-AB Power Control boxes. Provides - space for two hex and two quad slot modules. Mounts in 1 SU. DD11-DK Nine-slot expansion backplane mounting unit for HSC95-AB Power Control KU/KV boxes or in PDP 11/84, 11/44, and 11/24 CPU - - boxes. Provides space for seven hex and two quad modules. Mounts in two SUs. The HSC95-AB Power Control-CK backplane allows a maximum 5 V usage of 16 A. The HSC95-AB Power Control-CK backplane allows a maximum 5 V usage equal to 24 A.