Pig-tail patch cord, also known as pigtail fiber optic patch cord, refers to a patch cord formed by installing fiber optic connectors at both ends of a ready-made pigtail cable. Pigtail cables are mostly single-core or dual-core structured, and can also be made into four-core structure, with an 8-shaped cross-section. The strength member is located at the center of the two circles, which can adopt metal or non-metallic structure, and the optical fiber is at the geometric center of the 8-shape. It features flexibility, small bending radius, and ease of construction and wiring. There are various types of connector joints for pigtail fiber optic patch cords, such as FC, SC, ST, LC, etc. The specifications of pigtail fiber optic patch cords can be customized, with common lengths like 3m, 5m, 10m, 20m, etc. Other lengths can also be customized according to requirements, usually ranging from 3 meters to 800 meters.