Self-Closing Non-Modular Octagons: 23

The self-closing boxes shown on this page do not have a separate lid and base. Made from a single sheet of paper, they collapse closed with a slight twisting motion; then pushing down gently on the center of the lid will lock it closed tightly.
 
Self-closing boxes may be made in many different shapes. The ones shown here all have an octagonal shape at the base and lids which are formed by eight overlapping flaps.
 
These boxes were designed by Phillip Chapman-Bell (Oschene) and Christiane Bettens (Mélisande), with a few variations of my own.