There are three types of overhead insulators: Pin, strain and suspension insulators. Unlike the others, pin insulators are directly connected to the physical support compared to being suspended from the wire. The pin insulator is used in power distribution for the voltage up to 33kV. A pin insulator is not usually used above 33kV, though construction of three or four-piece insulator may be possible but not usually due to the size becoming too bulky and the high weight which would not prove to be economical.
The advantages of an insulator pin are that it has a high mechanical strength; the pin type insulator has good creepage distance. It is normally used vertically but can be used horizontally as well.
Insulator pins come in a variety of sizes from 50mm to 150 mm, one type of pin can be used to hang multiple types of noise insulation, reducing inventory needs.