Lock off units have the ability to be split into 2 separate units or even 2 separate weeks.
For example, a 2 bedroom, two bath unit could be separated in to two one bedroom units for one week. Some clubs allow owners to split your week in your 2 bedroom for 2 different weeks in a 1 bedroom, allowing you to book two different times of the year. This can be a great feature for booking flexibility, but it can also aid in maintaining privacy when traveling with two couples or multiple families.