They are designed to provide SDH SFP compliant links for both

Designed for switch vendors and operators alike, the MiRICi-155 is housed in a standard SDH SFP package complying with the Multi-Source Agreement (MSA). This enables the MiRICi-155 to be plugged into any Gigabit Ethernet device with a regular MSA-compatible socket. Deriving power from the host device, it requires no additional electricity and offers significant savings in space, cabling and power consumption.Cisco offers a range of SDH SFP. Products include OC3/ STM-1, OC12/STM-4, and OC48/ STM-16 SFPs for multimode, short reach, intermediate reach, long reach (40km), and long rach (80m) applications.The SFP are compatible  with the SDH SFP and ATM standards, and support the digital diagnostic functions specified in the SFF-8742 Multi-Source Agreement (MSA) and the extended operating temperature range from 23 to185°F (-5 to 85°C).OC-3/STM-1 is a network line with transmission speeds of up to 155.52 Mbit/s (payload: 148.608 Mbit/s; overhead: 6.912 Mbit/s, including path overhead) using fiber optics. Depending on the system OC-3 is also known as STS-3 (electrical level) and SDH SFP. These modules are also used for Fast Ethernet application.