Timetec Hynix IC 8GB Compatible for Apple DDR3L 1600MHz PC3L-12800 SODIMM Memory Upgrade for Early/Mid/Late 2011, Mid/Late 2012, Early/Late 2013, Late 2014, Mid 2015 MacBook Pro, iMac, Mac Mini (8GB) : Amazon.co.uk:
recommended ram for mid-2012 macbook pro - Apple Community
MacBook Pro: how to remove or install memory – Apple Support (UK)