Premium Domestic Ball Point Sewing Machine Needles by Groz Beckert can be purchased by the single needle or in bulk quantities too.
Which number needle do I need for which type of fabric?
8 / 60: Very fine silks, synthetics and cottons
10 / 70: Lightweight fabrics, net, chiffon, sheer nylon
11 / 75: Medium weight fabrics – Voile, Chiffon, Organza
12 / 80: Cotton lawn, taffeta, silks, tricots
14 / 90: Medium heavyweight fabrics, poplin, chintz, velvets
16 / 100: Heavy weight fabrics, cord, denim, gabardine, heavy suiting
18 / 110: Upholstery fabrics, denim, leather
20 / 120: Heavy Canvas and denims