A 5 I bought two of these caps for the summer period.They arrived the very day after I placed the order.They are even softer and more comfortable than I expected.I am using one in the house (grey color) and one for going out (black).They are knitted like a tube so you can use them in several ways (even as a mask) and they can be used comfortably also by those with long hairs.So far I like them and I'm happy about the purchase.