To send as a letter size the a4 sheets will be folded making 10x a5, or 5 folded a4 sheets.
Model Railway concrete texture Sheet A5 self adhesive x4
MODEL RAILWAY LAYOUT TEXTURE MODELLING : BEST PRACTICE TIPS & TECHNIQUES BOOK
Model Railway cobblestone texture Sheet A5 self adhesive x4 (SCS)
Model Railway cobblestone texture Sheet A5 self adhesive x10 (SCS)
Model Railway cobblestone texture Sheet A4 self adhesive x2 (scs)