Portfolio 23 x 32 cm, with flaps to keep documents from sliding out. Large enough to hold A4 sheets without folding or creasing. It will expand to 2 cm thickness. 

Covers are the clover design by Angie Lewin,  designed for a fabric, which you can still buy from St Judes

The portfolio has a robust construction with the spine and flaps made using library buckram - a very durable bookcloth.