The 'Braided Cable' chain is (45cm/18") This length works really well for most high necklines - including turtle necks and boat necks. It's also an elegant choice for evening wear. Depending on the length and your build you may also be able to wear an opera length wrapped around your neck more than once to form a double stranded collar or choker.
All chain Pictures shown may not be identical and may vary due to product stock, or the clasp. Measurements are approximate.