Our sheets are serged in the four corners, so wash and dry them as much as you need. We've also put elastic around the entire edge of the sheet. The pockets are plenty deep, so our sheets fit all standard 28" x 52" (ish) mattresses.
This particular listing includes one fitted crib sheet in black triangles, an exclusive Iviebaby design.
If you'd like another fabric or a special size, just ask us!