This is an example of a compliant device. It is printed in TPU in one piece. The flexible fulcrum allows force to travel from the stiff handles to the stiff jaws.
The advantages are a low part count … The disadvantage is the slight flexibility in the jaws, which makes the pliers less efficient… Materials that are sufficiently stiff and resistant to fatigue can be suitable for such applications.
For more information on compliant mechanisms see https://www.compliantmechanisms.byu.edu/about-compliant-mechanisms
This 3D printed object was reproduced for 3D printing education.