Most modern pliers have the jaws coming together at an angle via a single joint, this older vintage design uses crossing leverage to bring the jaws together in parallel, which is very useful in a lot of circumstances. The jaws are also knurled to increase gripping traction.

The assembly is a little difficult but not too challenging. You will absolutely want to print with supports as there are serious overhangs inside the handles. I used auto tree supports without any problems.

When pushing the pins into their respective sleeves, do so slowly to avoid breakage. It's also good to check them for filament artifacts since the tolerances are so small.