OWC 4GB UPGRADE: Consists of a single 4GB DDR3 1600 PC3-12800 CL11 2Rx8 204-pin 1.5V SODIMM Memory RAM Module Upgrade memory module compatible with QNAP models IS-400 Pro, TVS-471, TVS-671 And TVS-871. 100% COMPLIANT: JEDEC-Standard and ROHS Compliant. Warranty-Safe Upgrade. Designed and Tested to Meet or Exceed all Manufacturer OEM Specs. EASY INSTALLATION: In Most Cases, Installing Memory is an Easy DIY project. Watch our OWC Basic Installation Video for Help. INDUSTRY LEADING: Consumer-friendly Advanced Replacement Program and Limited Lifetime Warranty, which includes Free Tech Support by Other World Computing. Replacement for QNAP part number RAM-4GDR3-SO-1600.