A set of essentially identical floor panels (1, 1', 1") each comprising long (5a, 5b) and short edges (4a, 4b) provided with a mechanical locking system comprising first and second connectors (9,10, 6,8,14) integrated with the floor panels, and wherein immediately juxtaposed upper parts of two adjacent joint edges of two joined floor panels together define a vertical plane perpendicular to the main plane of the panels, the first connector comprises a locking strip with an upwardly directed locking element, at a first edge of a floor panel, configured to cooperate with a downwardly open locking groove at an adjacent second edge of another floor panel for connecting the adjacent edges in a horizontal direction perpendicular to the vertical plane, the second connector comprises a tongue at the second edge, extending horizontally perpendicular to the vertical plane, configured to cooperate with a horizontally open tongue groove at the first edge for connecting the adjacent edges in a vertical direction parallel to the vertical plane, the connectors at the long edges are configured to be locked with angling and the connectors at the short edge are configured to be locked with vertical snap folding, whereby a long edge of a new panel in a second row R2 is configured to be connected to a long edge of a first panel 1'' in a first row R1 by angling, whereby a second short edge of the new panel and a first short edge of a second panel in the second row R2 are configured to be connected with the same angling motion, wherein the tongue at the second short edge is formed in one piece with the panel and protrudes from a substantially vertical upper surface at said one short edge, wherein the locking strip at the short edges (4a, 4b) is bendable, to obtain a resilient bending during the vertical snap folding action, which bending facilitates the assembling of the tongue and the tongue groove, wherein the first and the second connector (9,10, 6,8,14) at the long edges are configured to obtain a minimum of friction facilitating a displacement of the new panel in the horizontal direction along the long edge during the vertical snap folding action and enabling a locking made with a hand pressure and without tools, wherein said displacement being realised by a spring back force from the bending of the short edge locking strip, and characterised in that the panels have a thickness and wherein the tongue on the short edge extends a tongue distance from the vertical plane which tongue distance is at least 0,1 time the floor thickness. wherein the tongue at the second short edge is formed in one piece with the panel and protrudes from a substantially vertical upper surface at said one short edge, wherein the locking strip at the short edges (4a, 4b) is bendable, to obtain a resilient bending during the vertical snap folding action, which bending facilitates the assembling of the tongue and the tongue groove, wherein the first and the second connector (9,10, 6,8,14) at the long edges are configured to obtain a minimum of friction facilitating a displacement of the new panel in the horizontal direction along the long edge during the vertical snap folding action and enabling a locking made with a hand pressure and without tools, wherein said displacement being realised by a spring back force from the bending of the short edge locking strip, and characterised in that the panels have a thickness and wherein the tongue on the short edge extends a tongue distance from the vertical plane which tongue distance is at least 0,1 time the floor thickness.