When placing two Kallax cabinets next to each other, they don't always align so well. This bothered me enormously, as any sane person would, obviously.
With this method you don't have to make any new holes, but just use the existing ones!
This connector piece hooks into the screw countersink that already exists. So before your insert the standard screws that come with your Kallax, place this connector in between. Before fully tightening the screws, make sure the two Kallax cabinets are aligned, hold it there, and tighten them all the way so they will retain their alignment.
I advise you to place a connector at both sides, not just the front or the back, so it's a little bit sturdier.
This is in general a great way to connect two Kallax cabinets. The connector could be mounted on the bottom of the cabinet as well.
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