A sheet material, for packaging pourable food products, comprising at least a first and a second layer, and having an opening formed through said first layer and sealed by a cover portion of said second layer;
- said sheet material also comprising an opening device made of plastic material, injection molded onto said cover portion, and in turn comprising, integrally, an attachment portion adhering to a first side of said cover portion, and a spout extending through a peripheral portion of said cover portion to project from a second side, opposite said first side, of the cover portion;
- said attachment portion defining, with said cover portion, a user-removable sealing portion of said spout.