The Harman Express site indicates that Direct Positive Paper item #1171158 is nominally 10.2cm X 12.7cm (4" X 5" Imperial) but actually measures 9.96cm X 12.5cm. This is the size that goes into standard 4x5 film holders. There used to be (still is?) a genuine 4"x5" DP paper that is a paper size, not a film size, and needs trimming to go into a film holder.