Remove the shaving heads 

1. Switch off the shaver.
2. Remove the shaving unit from the shaver. 
3. Turn the wheel anticlockwise (1) and remove the retaining frame (2) (Fig. 1).
   Note: Do not clean more than one cutter and guard at a time, since they are all matching sets. If you accidentally mix up the cutters and guards, it may take several weeks before optimal shaving performance is restored.
4. Remove the cutters and guards from the shaving unit (Fig. 2). 

Place the shaving heads back

1. Put the cutters back into the guards (Fig. 3)
2. Put the shaving heads back into the shaving unit. (Fig. 4)
   Make sure the projections of the shaving guard (marked green in the picture) fit into the recesses in the shaving unit. 
3. Put the retaining frame back into the shaving unit, push it down (1) and turn the wheel clockwise (2) (Fig. 5)
4. Check if the retaining frame is locked. (Fig. 6). 
5. Put the shaving unit back onto the shaver.