In the D3 modular system, all A4 and A6 modules are optionally equipped with individual locks. In addition, customers may opt for a central locking mechanism at the time of order. In this case, the modules are vertically connected and up to five stacked modules can be locked using the same mechanism. Now, it is also possible to choose the central locking option for drawers and cable guides (including utensil drawers).

The solution's modularity is in no way limited by the use of central locking. Locks can be placed precisely where the user needs them and modules can be rearranged at any time.