If it is needed to press a top stop on a zip fastener only occasionally, simpler crimping pliers can also be used. Compared to the professional Osborne pliers, its jaws made of simple structural steel are narrower and thinner. With frequent use, thin structural steel therefore wears faster on the jaws and at the joint. The jaw surfaces are often improperly aligned with each other, which is why it is more difficult to grip and hold the small top stop.
The spring tension opens the pliers. That is why you need to handle the pliers after inserting the top stop with well-measured pressure, so that the top stop does not fall out of the pliers before you have pressed it on the zipper tape. Using these pliers does not require many skills. At least you can press the smaller top stops quite neatly, as shown in the accompanying pictures.