TYRE FOR VEHICLE WHEELS

Tyre for vehicle wheels, comprising a tread band comprising circumferential grooves, circumferential ribs defined by said circumferential grooves and a plurality of sipes () that extend, on said circumferential ribs, from a radially outer surface of the tread band towards a radially inner portion of the tread band. Said sipes () extend along a predetermined trajectory and comprise, in any cross section perpendicular to said predetermined trajectory, a main portion () having a first radial dimension (H′) and a first transversal dimension (T, T′) substantially constant along a radial direction and, in a radially outer position with respect to said main portion (), a top portion () extending up to said radially outer surface of the tread band and having, at said radially outer surface of the tread band, a second transversal dimension (W) greater than said first transversal dimension (T, T′).