SANDISK A110 256GB M.2 SSD 2260 for Hp Zbook G2, 820 G2, 840 G2, PN: 759492-001 £53.99 - PicClick UK
22*42mm M.2 Ssd 128gb Full 118gb Sata Iii 6gb/s Internal Hard Drive M2 Ssd Ngff For Chromebook Acer C720 For Hp Ellitbook 840 G1 - Internal Solid State Drives - AliExpress
HP EliteBook 840 G2 - Specs, Tests, and Prices | LaptopMedia.com