Medium to advanced skills. You need yarn (Marks & Katten Eco Baby Ull or Senjagarn, both Sport, 5 ply, 12 wpi. Medium size 250 gram, 905,3 meters or 990 yards, in small size you need 25 gram less and in large size you need 50-100 gram more) and needles (4 mm/US 6). Knitted both in the round and back and forth. Three sizes: small, medium and large.