A set of panels including a first panel and a second panel. A first edge of the first panel and a second edge of the second are configured to be locked together and assembled by a vertical displacement of the second edge relative the first edge. The first edge includes a locking element configured to cooperate with a locking groove at the second edge for locking in a horizontal and in the vertical direction. The first edge includes a tongue configured to cooperate with a tongue groove at the second edge for locking in a vertical direction. An upper part of the first edge includes a first guiding surface and a lower edge of the lower lip includes a second guiding surface. An upper part of the locking element includes a third guiding surface and a lower edge of the locking groove includes a fourth guiding surface.