Taken from machines during memory upgrades. Fully tested and working with Memtest. 4GB kit consisting of two 2GB modules. Modules within a pair will always be the same model. Suitable for DDR3 laptops after 2012, (Intel 2xxx - 4xxx processors). If your laptop is older than 2011. 2012 - Mid 2015 Apple 27 inch iMac 2012 Mac Mini .