Not all fiber optic pigtails have round tips; the tip shape depends on the connector polish type, such as UPC (flat/round) or APC (angled).

Fiber optic pigtails are short lengths of optical fiber with a factory-terminated connector on one end and a bare fiber on the other for splicing . The connector end is polished to ensure low insertion loss and high return loss, but the tip shape varies depending on the polish type. Common polish types include:

• UPC (Ultra Physical Contact): The fiber end is polished flat or slightly curved (round) to minimize back reflection, commonly used in data centers and telecom networks .
• APC (Angled Physical Contact): The fiber end is polished at an 8-degree angle, producing a slanted tip rather than a round one, which reduces back reflection even further, often used in FTTH and high-precision applications . Connector types such as LC, SC, FC, ST, MU, and E2000 can be manufactured with either UPC or APC polish, meaning the tip shape is not universally round . The choice of polish type affects network performance, compatibility, and the type of equipment the pigtail can connect to. In summary, fiber optic pigtails do not all have round tips; the tip shape is determined by the connector's polish type, with UPC tips typically round or flat and APC tips angled. Selecting the correct tip type is essential for minimizing signal loss and ensuring proper network operation .