Mend-A-Fuse.
Small fusewire card with only two types of wire - 5A and 15A.
Since the majority of houses would have at least one 30A circuit, not providing 30A wire is a significant omission.
The case is made from Salpa or bonded leather - a sheet material essentially made from leather dust and glue.
The whole idea of making a case to put fusewire into seems irrelevant as well - since most fusewire would be shoved under the stairs next to the fusebox and seldom seen or used.