It is compatible with all models and brands of flat family sewing machines. There are 5 needles in each package. 2 packages no. 9, 2 packages no. 11, 2 packages no. 14 will be sent. No. 9 is used for thin fabrics, no. 11 for light fabrics such as combed cotton, no. 14 for medium thickness fabrics. It is an original Singer machine needle.