This screwdriver contains three small spools of fusewire inside the plastic handle.
This was probably a promotional item, as the handle contains the remains of the wording 'Presented...'. As with the stripmaster, probably more of a novelty item rather than one intended for regular use.
Here, the small spools of fusewire have been removed from the handle.
Values are 15A, 10A, 5A.
The red plastic fusewire holder also forms the end of the handle.
It is marked VITREX FUSEMASTER No.505 and includes a metal hanging loop.
The blade stem has details of a provisional patent / patent pending.