WD 1TB RED NAS Compatible Hard Drives - WD10EFRX
WD 2TB RED NAS Compatible Hard Drives - WD20EFRX
approx. $156 USD
WD 3TB RED NAS Compatible Hard Drives - WD30EFRX
approx. $206 USD
WD 4TB RED NAS Compatible Hard Drives - WD40EFRX
approx. $272 USD