I think it was "R.H." who stated:

The latest set has just been posted:

http://puzzlephotos.blogspot.com/

Number 780 is an audio tape splicer for 1/4" tape. The "CUT" position
makes a diagonal cut on the tape, and after the cut ends are spliced
together with splicing tape, the "TRIM" position cuts the edges of the
tape with a slight inward taper from both edges so that the splice
will slide easily through the player when it's played.
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