As sewing product from nature, cotton thread is not as strong as polyester, when you need strong all purpose thread for sewing and quilting, welcome to choose Simthread All Purpose Thread Polyester 400 Yards There are 22colors available These all purpose thread polyester has the cotton feel, with less lint, a good choice for your sewing projects. Besides, we also have heavy duty thread for sewing, especially for outdoor sewing project. 100 long staple Mercerized Cotton for stronger, more lustrous finish. Mercerized processing which produces a smoother thread with less lint Sets includes 12 neutral colors for daily usage. Thread size 50s/3, which is also called 50WT 3 Plies (Tex 35, 30WT), 550 yards each spool. We produce them according the thread length and weight. We supply these cotton sewing threads raw material to Germany, 100 Quality Guarantee Extra Long Staple Cotton -- a great all-purpose cotton thread. People love it for sewing, piecing. Many love it for quilting - machine or hand. Some love it for embroidery. You can test that they are made of cotton by burning it with ashes Environment Friendly for common sewing for baby clothes etc, fits standard sewing machine spindles, this cotton thread set can be used as quilting threads, cotton embroidery threads etc.