Alcatel-Lucent Nokia Original 1.25G to 2.67G SFP Transceiver. A rugged, industrial-temperature optical module designed for SONET OC-48, SDH STM-16, and Optical Transport Network (OTN) legacy transport architectures. Operates at a 1310nm intermediate-reach (IR) wavelength over Dual Single-Mode Fiber (SMF) via a duplex LC connector, supporting communication distances up to 15km. Features full Digital Optical Monitoring (DOM/DDM) and heavy-duty ambient resilience ($-40^\circ\text{C}$ to $+85^\circ\text{C}$) for outdoor enclosure deployment