HP A3231-69007 - 10 slot midplane board - 10 Slot Midplane Board - Vertical Interconnect Board (in the Center of the Disk Array) Retail
HP A3232-69107 - 20 slot midplane board - 20 Slot Midplane Board - Vertical Interconnect Board (in the Center of the Disk Array) Retail
HP A6961-67105 - Midplane riser board - Has slots for the processor board, memory board, and I/O base board Retail