100G QSFP28 ELR4 transceiver modules are designed for use in 100 G Ethernet links on up to 20km of single-mode fiber. They are compliant with the IEEE 802.3-2018 CAUI-4, QSFP28 MSA, SFF-8661 Revision 1.9, and SFF-8636 Revision 2.10a. Digital diagnostics functions are available via the I2C interface, as specified by the QSFP28 MSA, to allow access to real-time operating parameters. RoHS-6 compliant per Directive 2011/65/EC. With these features, this easy-to-install, hot-swappable transceiver is suitable to be used in various applications, such as 100G telecom connections, data center, high-performance computing networks, enterprise core and distribution layers, campus networks, etc.