Patent attributes
Building panels including a locking system for locking of a first edge portion to an adjacent second edge portion. The locking system includes a tongue and a tongue groove configured to cooperate for vertical locking. The tongue groove includes an upper and a lower lip protruding horizontally beyond the upper lip. In a locked state of the building panels an outer end portion of a lower vertical locking surface of the tongue is provided horizontally closer than an outer end portion of an upper vertical locking surface of the upper lip to a locking element provided on a strip extending beyond an upper portion of the first edge portion. Alternatively, or additionally, an inner end portion of a lower vertical locking surface of the lower lip is provided horizontally closer than an inner end portion of an upper vertical locking surface of the tongue to the locking element.
