Three Die Set for Straight Wall Cases - Three Die Set for straight wall cases contain three dies. This is necessary because it is not possible to full length resize straight wall cases and expand the neck fro proper bullet fit in one operation. The full length (FL) resizing die contains a decapping road assembly. The expander die (EXP) contains a neck expanding plug. The seating die (ST) includes bullet guide, built-in crimp ring and proper seating plug.