Every knitter should have a Needle Size Gauge! A useful accessory for measuring needle sizes and tension gauge.
Measures needles from 2mm to 12mm (US 0 to US 17). Also includes a 6″ (14.5cm) ruler, and see-through & magnified section for counting stitches and rows, especially for a 4″ / 10cm tension square Size – 21/4″ x 61/2″ (55mm x 160mm). Brand – KnitPro.