This field is the Z axis SAFETY PLANE to which the tool retracts to between CUTS, or after a cutting cycle. The code generated will have a Z move to this location in rapid, then a Z move to the feed distance to material (parameter #29 in Modify Tool page), and the next Z axis move will have a feed rate attached to it. After CUTTING, the code will generate a move back to this location and then proceed either to the next Cut or to the next tool, etc.
NOTE: Placing an asterisk (*) in this field before the value will ensure that the move is absolute, instead of incremental. For instance using *0.25 will return the cutter to .25 above Z0, however, using 0.25 (no * ) will return the cutter to a point .25 units above the last Z position only.