Quality rubber bands. Without insulation. The seller has probably 'shifted' the data of the recommended foot length in cm for individual numbers on the pages in the table. I am stating the actual data written off from the elastics, because the seller ignored my request to correct the chart: EU number 42 = JPN 26.8cm + oversize EU number 43 = JPN 27.9cm + oversize EU number 44 = JPN 28.3cm + oversize The length of your foot should sit with Japanese numbering. The actual length of the insole = JPN numbering + oversize The oversize is about 1cm, which is ideal space for foot movement or thicker socks.