Your fitted sheet is worn out but the flat and pillowcases still new! It's very common that fitted sheet wears out much sooner than flat sheet and that is due to that fact that fitted sheet is subjected to body and feet friction much greater than flat sheet. Our Top Split King Fitted Sheet 340 Thread Count 100% Pure Cotton gives you the option to just replace only what you need. 

Dimensions 

Top Split  King Fitted Sheet 78 inches wide X 80 inches long, The Split-Top Fitted sheets has a 32-inch split from the top to the middle and is made with 6 corner pockets to fit 15 inches deep.