ORDER HELPLINE\n\nNot sure what you are looking for?\nEmail us for friendly advice:\nContact Us\n\nMenu\n\n--Power Supplies\n\n--Storage\n\n--RAM Memory\n\n--CPU Cooling\n\n--PC Cooling\n\n--Peripherals\n\n--Power Cables\n\n--PC Cases\n\n--Graphics Cards\n\n--Processors\n\n--Motherboards\n\n--Monitors\n\n--View All Items\n\n--About Us\n\n--Contact Us\n\n--Feedback\n\n\u25CF\n\u25CF\n\u25CF\n\nSynology D4ES01-4G \u2014 4GB DDR4 ECC Unbuffered SODIMM\nThe Synology D4ES01-4G is an official Synology memory module designed and validated specifically for 21-series NAS enclosures. DDR4 ECC technology protects your NAS data from memory errors in real time \u2014 making it the trusted choice for expanding RAM in the DS1821+, DS1621+, RS1221+, and RS1221RP+.\n\nOfficial Synology RAM\n4GB DDR4 ECC\nUnbuffered SODIMM\n5-Year Warranty\n21 Series\n\nCapacity\n4GB\nPer module\n\nType\nDDR4\nECC Unbuffered\n\nForm Factor\nSODIMM\nSmall outline DIMM\n\nWarranty\n5 Yrs\nSynology official\n\nCompatibleb