These needles were designed for use in electronic multi-purpose sergers that do the overlock, cover, safety and mock safety stitches. They are the perfect sewing partners for your needlework project! Details: Silver 3.7'' x 2.3'' package size Not for use in normal home sewing machines or embroidery machines For us with machines that specify ELX705 system Imported Contents: 5 universal serger machine needles (size 80/12)