OWC 4GB UPGRADE: Consists of a single 4GB DDR3L 1866 PC3L-14900 CL13 1Rx8 204-pin 1.35V SODIMM Memory RAM Module Upgrade memory module compatible with QNAP models TS-253B, TS-253Be, TS-453B, TS-453Be And TS-453BT3. 100% COMPLIANT: JEDEC-Standard and ROHS Compliant. Warranty-Safe Upgrade. Designed and Tested to Meet or Exceed all Manufacturer OEM Specs. INCREASED PERFORMANCE: Memory Upgrades are the Most Effective and Easy Way to Boost your PC's Performance. INDUSTRY LEADING: Consumer-friendly Advanced Replacement Program and Limited Lifetime Warranty, which includes Free Tech Support by Other World Computing. EASY INSTALLATION: In Most Cases, Installing Memory is an Easy DIY project. Watch our OWC Basic Installation Video for Help.