MacBook Air 11 inch 2012 can not upgrade RAM and SSD
MacBook Air SSD Memory Chip - 661-6619 661-6620
Apple MacBook Air 11-inch Review | 2012 | Digital Trends
A-Tech 8GB RAM for Apple MacBook Pro (Mid 2012), iMac (Late 2012, Early/Late 2013, Late 2014, Mid 2015), Mac Mini (Late 2012) | DDR3 1600MHz PC3-12800 SODIMM 204-Pin Memory Upgrade at Amazon.com
MacBook Air (11-inch, Mid 2012) - Technical Specifications
A-Tech 8GB RAM for Apple MacBook Pro (Mid 2012), iMac (Late 2012, Early/Late 2013, Late 2014, Mid 2015), Mac Mini (Late 2012) | DDR3 1600MHz PC3-12800 SODIMM 204-Pin Memory Upgrade at Amazon.com