An essential part of pliers is the joint. You can make a distinction between the following styles of joints:
The two plier halves lie on top of each other but are not milled out.
Half the thickness in each pliers handle is milled away in the joint area so that both handles can be laid into each other.
One handle on the pliers is slit. The other handle is pushed through this slot. This joint connection can withstand a high level of load and strain because the joint bolt is supported on both sides and the inside handle is double.