1 2 3 4
E E E E
* X u v
  * v u
    * t
      *
handedness 1 2 3 L
handedness 1 2 4 R
handedness 1 3 4 R
handedness 2 3 4 R
sheetS 3 4
sheetD 1 2
sheetD 1 3
sheetD 2 3
length 1 E 5 100
length 2 E 5 100
length 3 E 5 100
length 4 E 5 100