A2 bend-insensitive single-mode optical fiber for FTTH, dense indoor routing, compact terminal boxes, and drone fiber or FPV tether systems. The experience with the installation and operation of single-mode fibre and cable-based networks is huge and Recommendation ITU-T G. 652, which describes its characteristics, has been adapted to this experience. Among these, commonly used standards are G. This article intends to provide a clear explanation of G.