Franklin Reiser

The yazh (Tamil: யாழ், also transliterated yāḻ, pronounced [jaːɻ]) is an harp used in ancient Tamil music. It was strung with gut strings that ran from an curved ebony neck to a boat or trough-shaped resonator, the opening of which was a covered with skin for a soundboard.

This is quoted from the Crocs com site: "THE PERFECT CROCS ™ FIT Crocs ™ should not fit like other shoes: They should fit very loosely The sides

When the wallet is open, the outer layer pops out making the hole visible (left) When you close it (right), the gap disappears as the outer layer is stretched to cover the bend It's the the same reason why the skin on your elbow has folds when you hold your arms straight and is stretched when you bend it