Samsung 16GB Desktop RAM (x2 8GB Sticks) - 1Rx8 PC4-2666V-UA2-11, HMA81GU6CJR8N. DDR4 ram sticks. Works well I just upgraded mine to 32 GBs. Lightly used for only about 3 weeks. They work great and are very good for gaming I just do too much in the background of games to have 16 GBs