Does it actually have 312 keys?

The 312 key keyboard above is a musical instrument. It has 312 keys, but from looking at the keyboard being used it seems like you press one and 2, 3 or 4 above it also get pressed down. I am not sure if that qualifies it as a 312 key keyboard. I could be wrong though as maybe it does create a different sound depending on which key down the line is pressed.

If any one knows I would be grateful to find out. Post a comment. There is one more video after the jump of this keyboard being used.