Synology DDR4 - module - 4 GB for RS2421+, RS2421RP+,...
Crucial 16GB DDR4 3200 MHz DIMM CL22 Memory
Kingston 8GB DDR4 2666MHz Module Memory
Kingston 16GB DDR4 2666MHz Module Memory
Quantity to buy of StarTech.com 7 Port USB C Hub - C to C & A