Regular Point Machine sewing needles are designed for domestic regular sewing machines. It is important to use the correct size machine sewing needle and this depends upon which fabric you choose.
Machine sewing needle sizes are always quoted in imperial and metric.
This guide may help you:
Size 9/70 Suitable for light fabrics, silk and taffeta
Size 11/80 Suitable for medium fabrics, cotton, linen and satin
Size 14/90 Suitable for medium to heavy fabrics, this is an ideal in between needle
Size 16/100 Suitable for heavy fabrics, denim, tweeds, curtain fabrics and soft furnishings
Regular point machine needles are available in individual size packs and multi size packs.