Transcend 4GB JM DDR4 2666Mhz SO-DIMM 1Rx8 512Mx8 CL19 1.2V (JM2666HSH-4G) 
 
Transcend's JetRam memory modules are manufactured with true ETT grade, brand-name DRAM chips that have passed Transcend's strict screening process and rigorous environmental testing. 
JM DDR4 2666Mhz SO-DIMM 1Rx8 512Mx8 CL19 1. 2V 
Which is essential for executing mission-critical or compute-intensive tasks, 
As it can greatly reduce the risk of computational errors, while at the same time increasing overall system stability