MasterPiece is a #50 Egyptian-grown extra-long staple cotton designed specifically for piecing . Piecing is the sewing together of 'pieces' or portions of your quilt. It is sometimes called 'Patchwork'. There are several piecing methods such as paper piecing, chain piecing (most common method of piecing), and strip piecing. We recommend piecing with a #50 cotton thread because cotton can be ironed on high heat. A quality #50 thread is also fine enough to lie flat in the seams and not add bulk. Precision designed for piecing. Ideal for piecing, hand and machine appliqué, detail quilting, bobbin thread, and lacework. Very smooth with virtually no lint. Lies flat and does not pucker at the seams.