New profiles of 40x40 mm cross-section have been added to the item MB building kit system's Series X 8, which has been awarded the "red dot design award" for its clear design. Now all conceivable profile variations are available with both covered and open profile grooves. With the new groove opener even covered grooves can also be easily opened wherever the functionality of the universal profile groove is required. This new groove opening tool removes the groove cover quickly and precisely. For example, the necessary space for the popular standard connecting set 8 can be made with one single stroke of the groove opener thus enabling the profile connection to be created as is the case with an "open" profile.