Keys NOT available on Number pad (17" ) are:- 6, 7, 0 ins, E531 E540 E545 W540 W545 T540 T550. so that's 6 different versions in total! THE KEYS ARE FROM A USED LENOVO LAPTOP. Keys NOT available on main keyboard are:- Escape, Delete, W, E, P, A, S, H, Enter, Left Shift, Z, B, N, M, Left Ctrl, PrtSc, Right Ctrl, Fn, Windows key, Left Arrow, Down Arrow, Right Arrow.
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