Vintage 3M Scotch Brand Splicing Tape Metal Tin Dispenser and splicer

Description

Both dispensers have tape in them and it looks good enough to use but I am not positive as I have never used splicing tape....
The cutter/trimmer has good edge on the blades.
Add-a-tape looks good. Never left the packaging it seems.
The refill roll shown in the images is wider than the tape in the dispensers. It will not fit them and I do not know for certain if it is tape to tape splicing tape.