Three-cut four-foot rice paper refers to cutting the whole four-foot rice paper horizontally into 1/3. The size of 4-foot whole rice paper is about 70cm* 130cm, and it is about 43cm*70cm after 3 horizontal slits.
Because there is a certain error in the exact size of different brands of 4-foot rice paper, "limited to 4-foot rice paper with 3 seams" means that it is roughly equal to this size.