A set of furniture components formed as rectangular panels (1,2) comprising a first and a second panel, wherein an edge of the second panel is insertable into a groove of the first panel, when main planes of the first and the second panel are arranged essentially perpendicularly to each other, to obtain a mechanical locking between the first and the second panel, when the second panel is displaced essentially perpendicularly to the first panel, wherein: said edge comprises a tongue groove and said groove comprises a separate and flexible tongue; the separate and flexible tongue is insertable into the tongue groove for locking said panels to each other in a first direction, which is perpendicular to the main plane of the first panel; the edge of the second panel is configured to cooperate with the groove of the first panel for locking said panels to each other in a second direction, which is parallel to the main plane of the first panel; a length direction of the separate and flexible tongue extends parallel with said edge and/or groove; the groove comprises an opening, two side walls (6b, 6c) and a bottom; the separate and flexible tongue is arranged in an insertion groove formed in a wall of the groove of the first panel, the insertion groove having an upper wall and an opposite lower wall; the separate and flexible tongue has an inner part mounted in the insertion groove and an outer part extending outside an opening of the insertion groove; characterized in that the flexible tongue is linearly displaceable inwardly towards a bottom of the insertion groove and outwardly into the tongue groove during locking; and that the insertion groove is inclined upwards with the opening closer to the main plane of the first panel than an inner part of the insertion groove, the insertion groove being inclined such that a linear extension of the lower wall of the insertion groove is located at or above the upper part of the opening of the groove, wherein the flexible tongue has two opposite displacement surfaces (3a, 3b) located between the inner and the outer parts, each of the two opposite displacement surfaces of the flexible tongue are displaceable against the upper and the lower wall, respectively, of the insertion groove during locking, inwardly towards the bottom of the insertion groove and outwardly into the tongue groove. said edge comprises a tongue groove and said groove comprises a separate and flexible tongue; the separate and flexible tongue is insertable into the tongue groove for locking said panels to each other in a first direction, which is perpendicular to the main plane of the first panel; the edge of the second panel is configured to cooperate with the groove of the first panel for locking said panels to each other in a second direction, which is parallel to the main plane of the first panel; a length direction of the separate and flexible tongue extends parallel with said edge and/or groove; the groove comprises an opening, two side walls (6b, 6c) and a bottom; the separate and flexible tongue is arranged in an insertion groove formed in a wall of the groove of the first panel, the insertion groove having an upper wall and an opposite lower wall; the separate and flexible tongue has an inner part mounted in the insertion groove and an outer part extending outside an opening of the insertion groove; characterized in that the flexible tongue is linearly displaceable inwardly towards a bottom of the insertion groove and outwardly into the tongue groove during locking; and that the insertion groove is inclined upwards with the opening closer to the main plane of the first panel than an inner part of the insertion groove, the insertion groove being inclined such that a linear extension of the lower wall of the insertion groove is located at or above the upper part of the opening of the groove, wherein the flexible tongue has two opposite displacement surfaces (3a, 3b) located between the inner and the outer parts, each of the two opposite displacement surfaces of the flexible tongue are displaceable against the upper and the lower wall, respectively, of the insertion groove during locking, inwardly towards the bottom of the insertion groove and outwardly into the tongue groove.