A set including a first panel, a second panel and a mechanical locking device for locking the first panel to the second panel. The first edge surface is facing the second panel surface in a locked position of the first and the second panel, the mechanical locking device includes a rod-shaped element at the first edge surface and an insertion groove at the second panel surface, the rod-shaped element is configured to be inserted into the insertion groove. A first locking groove at the first edge surface and a second locking groove at the second panel surface and a locking part, where the locking part is configured to be inserted into the first locking groove and the second locking groove. The locking part is configured to apply a locking force between the first and the second panel in an oblique direction in relation to the second panel surface.

A joining system for furniture is provided. The joining system comprises a first furniture element and a joining element. The joining element has a width between a first and a second surface in the area of the second engaging portion. An increase in the width causes a first engaging portion to press harder on a first stabilizing portion which causes a male coupling portion to bend in a direction towards the surface comprising the second stabilizing portion to compensate for the increased width.

A joining system for furniture is provided. The joining system comprises a first furniture element and a joining element. The joining element has a width between a first and a second surface in the area of the second engaging portion. An increase in the width causes a first engaging portion to press harder on a first stabilizing portion which causes a male coupling portion to bend in a direction towards the surface comprising the second stabilizing portion to compensate for the increased width.