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Crucial Ballistix Sport LT 4GB (1x4GB) CL16 DDR4 2666MHz SODIMM Laptop Memory for the price of £17.99 delivered at Crucial
Specs - DDR4 PC4-21300 • CL=16 • Unbuffered • NON-ECC • DDR4-2666 • 1.2V • 512Meg x 64 •