The Fracture bounds rollout contains parameters for the “fracture bounds” fracture mode.
Mode: controls whether the bounds fracture operation will compare the length of the specified fracture axis to the length of the next-shortest fracture axis (and compare that ratio to the specified length ratio thresh), or compare the length of the specified fracture axis to the specified length threshold directly.
Axis: controls which OOBB axis will be used for the bounds fracture computation.
Length thresh: the initial number of slices will be computed by dividing the length of the specified object-oriented bounding box axis by this value.
Length ratio thresh: the initial number of slices will be computed by dividing the ratio between the length of the specified object-oriented bounding box axis and the length of the next-shortest object-oriented bounding box axis by this value.
Max slices: the maximum number of slices that will be assigned to a mesh along the primary object-oriented bounding box axis.