The 'Deep Pocket' classification for these sheets is true!  I have an adjustable bed, supplemented with a 3-inch foam topper, so regular sheets will not do the job.  This fitted sheet is so deep that I am able to tuck at least 10 additional inches UNDERNEATH the mattress.  No kidding.  I actually had to lift up the edges of the mattress to tuck the additional material underneath.  I love the quality of the elastic binding.  It's more than an inch wide.  I was disappointed that the stitching shrank after washing and drying.  So the material at the head of the sheet was rather crinkled up.  They should have pre-shrunk the thread prior to stitching.  The material itself is quite soft and excellent quality.  I consider it luxurious.