Super Deep Pocket Solid Black King Sheet Set 100%Cotton 600 Thread Count fit up to 21 inch mattress by sheetsnthings Experience true luxury when you sleep on these solid cotton sheets 600 thread count. super deep pocket fitted sheet fit up to 21 inch mattress with elastic all around for proper fit Set includes flat sheet, fitted sheet and two pillowcases 600 thread count.Thread count is the number of threads per square inch of fabric--the higher the thread count, the thicker, more durable and longer lasting the material machine wash.Softness enhansed with each washing