Domestic sewing machines today basically use the one needle system (705/130H, HAX1, 15X1) but they are available in a large variety of sizes and point styles. Selecting the right needle and thread for the fabric you plan to sew is one of the most fundamental steps to achieving a successful stitching result. Machine Needles come in sizes ranging from sizes Metric Size 60 to 120 (Imperial Sizes 8 to 20). This size essentially represents the thickness of the needle. The lower the number, the finer the needle. Thread, however, is the opposite, the finer the thread, the higher the number. When sewing, the thread lies in the needle groove, if the needle is too fine for the thread, the thread will not fit into this groove causing faulty stitching. The needle must also be in perfect condition. Stitching problems occur from using a needle that is either blunt, bent or if the tip has been damaged.