WC Apple Qualified For the Mac Pro 8-core / Quad-core Xeon Size: 4GB (4096MB) per module Technology: DDR2 ECC Pin Count: 240-pin FB-DIMM 512M x 72, Dual Rank ECC Module CAS 5-5-5 TRUE PC6400 DDR2 Major Thermal Tested Module Bandwidth: 6.4GB/s Fully compliant with all Apple Mac Pro Specifications Data Rate: 800MHz Speed: PC6400 Voltage: 1.8V Fully compliant with JEDEC specifications RoHS Certified