The Cisco QSFP-40G-LR-S= is an optical transceiver module compliant with 40GBASE-LR4, designed to operate over single-mode fiber (SMF) at distances up to 10 kilometers [1, 3]. The module uses four wavelengths in the 1310 nanometer range and supports a data transmission rate of 40 gigabits per second [1, 3]. Specifications for the Cisco QSFP-40G-LR-S=: Type: QSFP (Quad Small Form-factor Pluggable). Data Rate: 40 gigabits per second. Maximum Distance: 10 kilometers over single-mode fiber (SMF) [1, 3]. Fiber Type: Single-mode fiber (SMF) [1, 3]. Wavelengths: Four wavelengths in the 1310 nanometer range. Connector: LC Duplex. Compatibility: Compliant with 40GBASE-LR4. Applications: Data centers, high-performance computing networks, and enterprise core and distribution networks. Additional Features: Hot-pluggability: The module is hot-swappable, facilitating easy installation and replacement. MSA Compliance: Compliant with Multi-Source Agreement (MSA) specifications. Digital Diagnostic Monitoring: Supports digital diagnostic monitoring functions (DOM). Low Power Consumption: Highly efficient in power usage. High Reliability: Designed to deliver reliable performance in various operating environments. Manufacturer: Original Cisco Condition: New Quantity: 30 units Price: 3500 SAR per unit