Upgrade your computer's memory with this 4GB DDR3 SDRAM module from Samsung. This module has a form factor of SO-DIMM and a total capacity of 4GB, with a capacity of 4GB per module. It is compatible with mini desktops and laptops that have 204 pins and a bus speed of PC3-10600 (DDR3-1333). This memory module features NON-ECC memory and is California Prop 65 Warning compliant. With the model number 4GB 2RX8 PC3-10600S-09-11-F3, this module is perfect for enhancing your computer's performance.

I have both 4GB DDR3 8500 SDRAM  and 4GB 2Rx8 PC3 10600S

These are used interchangeably.