Our automatic cassette loading machines use full rolls of splicing tape to splice together 1000s of joints between the magnetic tape and leader tape and when it's time to change over to a new full reel it leaves a short amount of splicing tape still on the end of the roll. Sometimes we change the roll before it has come to and end to avoid downtime and /or wastage on a longer run so some roll ends have enough splice left for around 20-30 more splices.
So instead of buying a full roll for £9 or £10 each and never using 95% of it then if you just need to do a few splices or repair a couple of broken tapes a roll end would be ideal.
Use a very sharp knife such as a razor blade to make a straight cut in the tape/leader
מק"ט: rollendsplice