ANSI class 56-1, 56-2 porcelain pin insulators are manufactured in accordance with ANSI C29.6 and ANSI 29.1, and are used on high voltage distribution lines of power system like other pin type insulators.

ANSI class 56-1, 56-2 pin insulators consist of a nonconducting material such as porcelain, glass, plastic, polymer, or wood that is formed into a shape that will isolate a wire from a physical support (or "pin") on a telegraph, utility pole or other structure, provide a means to hold the insulator to the pin, and provide a means to secure the conductor to the insulator.

ANSI class 56-1, 56-2 porcelain pin insulators feature extra skirts or wide shells to increase the surface distance between the conductor and the pin to provide isolation from moisture in open air. The "pin" is typically a wooden or metal dowel of about 3 cm diameter with screw threads. The ANSI class 56-1, 56-2 porcelain pin insulators has threads so that it can be screwed onto the pin.

A typical composite pin type insulator is more than 10 cm in diameter and weighs one kg or more. Size depends on the voltage to be isolated and the weight of span of wire to be supported. ANSI class 56-1, 56-2 porcelain pin insulators has been selected and bought by many customers.