Biro on a string

Biro on a String
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Biro with a loop to tie it with string to your clipboard, work bench or public notice board so that you do not lose it!
Comfortable triangular shape.
It takes an ink cartridge from a Bic Biro or a generic with a 4mm diameter collar behind the nib.
Print this with transparent filament so that you can see when the ink will run out.
The optional cap also has a loop. You may need to scale the cap if it is too tight or too loose depending on your printer and filament type.