US Patent 11703072 Set of panels with a mechanical locking device

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 panel includes a first edge surface and a first panel surface, the second panel includes a second panel surface, the first edge surface facing the second panel surface in a locked position of the first and the second panel, the mechanical locking device includes a panel groove at a surface of the second panel, a flexible tongue positioned in the panel groove, a rod-shaped element at the first edge surface and an insertion groove at the second panel surface extending from the second panel surface to the panel groove, the rod-shaped element having a first part at a first end, a second part at a second end and a recess in the second part, and a third part located between the first and second part.