Object Enablers are Advanced Logic Cubes used to hide models.  Object Enablers have a unique yellow orb that connects directly to models, thus allowing for builders to make their models disappear in-game, allowing for the making of doors and disappearing platforms.  When a model is hidden, a blue outline of it is put in its place, which can be removed by a user if he/she opens the options menu by right-clicking the Object Enabler and selecting the "Settings" option.  One Object Enabler can be attached to multiple models. Object Enablers can be attached to moving platforms, sentry bases, rotating models, and vehicle models as well.

An Object Enabler


The GUI menu for an Object Enabler (click to expand)