RAM & Memory Upgrades
32GB (2 x 16GB) DDR3 1333MHz PC3-10600 240-PIN ECC REGISTERED DIMM (RDIMM) MEMORY RAM KIT COMPATIBLE WITH MAC PRO (MID 2010-2012)
SIZE/CAPACITY: 32GB KIT (2 x 16GB) VOLTAGE/POWER CONSUMPTION: 1.5v CAS LATENCY: CL9 SPEED: PC3-10600 (1333MHz) TYPE/INTERFACE: 240-PIN DDR3 ECC REGISTERED DIMM (RDIMM) 240-PIN MAC PRO DDR3 ECC REGISTERED DIMM RDIMM KIT
https://www.bizrate.co.uk/ram_memoryupgrades/32gb-2-x-16gb-ddr3-oid7867076583.html