Specifications:
4GB, PC3-14900, DDR3-1866, 1866Mhz, 8.5GB/s Bandwidth, CAS 7-7-7-20, ECC, Dual Rank, RoHS Certified, 512x72, Unbuffered, 1.5V, 240pin DIMMs. Contains one (1) 4GB DRAM memory module that is specifically designed and SPD configured for the 2013 Mac Pro Model.
This DIMM contains the Apple Specified Thermal EPROM Sensor.
Installation Guide for 2013 Mac Pro RAM Upgrade
The following installation video covers the Mac Pro DDR3-1866Mhz.
Click here to find Apple's installation guide for the 2013 Mac Pro.