Stanley STST14027 SortMaster Organizer is a single organizing unit that features NEW side latches locks which allow the user to securely stack multiple organizers together. This allows transport of two units at once. The SortMaster offers removable dividers that provide high customization for small parts and larger hand tools, which allows for up to 1024 different configurations. A unique 90 degree angle design allows storage of hammers and angled tools, along side small parts. This organizer also features a special lid structure; lid interlocks with the dividers to keep all smarts parts securely stored inside, and to prevent movement of small parts from one compartment to another.