Style of Joints
An essential part of pliers is the joint. You can make a distinction between the following styles of joints:

Lap joint:

The two plier halves lie on top of each other but are not milled out.

Single joint:

Half the thickness in each pliers handle is milled away in the joint area so that both handles can be laid into each other.

Box joint:

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.