This one, the 55Y9003 is the exact same as the T420 keyboard. I have one, it's really nice, although some reinforcement and a Bluetooth version would really be appreciated. Alas it's really hard to take it apart. You can find instructions at https://forums.lenovo.com/t5/Displays-Options-and-Accessorie... and this forum post mentions some success in adding a few metal rods. http://forum.thinkpads.com/viewtopic.php?p=710896&sid=5322c4...