Two files are included. The "FPD" file is a Schaeffer "Front Panel Designer" file which can be opened in that free, downloadable (see Front Panel Express service online) utility, then optionally modified and then printed. The "PDF" file is an Adobe Acrobat file resulting from printing the "FPD" file, and it may be opened in any PDF application and printed at 100% full scale.

To use with the keycaps on the pushbutton switches referenced in the "Digi-Key conformed" version of the Single Board Relay Computer bill of material (BOM) .....which are different from the switches specificed in the original BOM........cut out each keycap label carefully 'just inside' the bold square borders, then apply permanent adhesive and carefully align with keycap and then press down to affix.

The layout of keycap labels on these files is the same as the actual keypad arrangement on the Relay Computer.