Design and Copyright : Gregory Benedetti (2012).

Pieces  4  AB, CD are congruent. Rounding edges. 
Selection  pair  
Goal  4×4×4  
Holes  8  
Solutions  2 / 2  
Moves  3  Rotation required. 
AAAC  D..C  D..C  DBBB AAAC  DBBB  AAAC  DBBB ACAC  DDDB  ACCC  DBDB ACCC  A..B  A..B  DDDB1. 2. 3. 4. 5.
AAAC  B..C  B..C  BDDD AAAC  BDDD  AAAC  BDBD ACAC  BBBD  ACCC  BBBD ACCC  A..D  A..D  BBBD