4GB STICK For Sony VAIO VPC F135FGB F135FL F136FD/B F136FG/BI F136FM F136FX F136FX/B F137FX F137HG F1390L F1390S F1390X CTO. SO-DIMM DDR3 NON-ECC PC3-10600 1333MHz RAM Memory. Genuine A-Tech Brand. 4GB STICK SO-DIMM DDR3 NON-ECC PC3-10600 1333MHz RAM Memory Genuine A-Tech Memory Lifetime Warranty Toll Free Technical Support 1-866-557-4527 Designed For Sony VAIO VPC. (See Compatibility List Below)