Pack of 100 Groz-Beckert Industrial Sewing Machine Needles. Needle system : TQX1 Equivalent needle numbers : 1985, 29-S, 175X1 These are the same exact needles under different names and numbers. *A needle system is a group of needles made to fit specific sewing machines. All needles in a system are of the same length and shank size, but are of various diameters. Lower size numbers are narrower or thinner needles used for lighter materials. Higher size numbers indicate a needle of thicker diameter, used for heavier materials. Match your needle system to your machine, then the size of the needle to the product you are sewing. Groz-Beckert TQX1 needles are available in following sizes. Please select your size. Singer Size 10 (Metric Size 70) for light to medium weight fabrics. Singer Size 11 (Metric Size 75) for light to medium weight fabrics. Singer Size 12 (Metric Size 80) for light-medium to medium weight fabrics. Singer Size 14 (Metric Size 90) for medium weight fabrics. Singer Size 16 (Metric Size 100) for medium-heavy fabrics. Singer Size 18 (Metric Size 110) for medium-heavy fabrics. Singer Size 19 (Metric Size 120) for heavy fabrics. Singer Size 20 (Metric Size 125) for heavy fabrics. Used on industrial button sewing machines and bartack sewing machines.