The Navico Ethernet Adapter Cable Green M12M 8-pin - Yellow 5-pin female (1.2 ft) works to connect yellow ended ethernet cables to the NEP-3 port expander.
Product Accessories for Navico Ethernet Adapter Yellow 5-Pin Female to Green 8-Pin Male

SKU: NVX12729
Navico 15ft Ethernet Cable
The Lowrance 15ft Ethernet Cable connects Lowrance HDS units to other Lowrance Network Devices.

SKU: NVX12751
Navico 6ft Ethernet Cable
The Lowrance 6ft Ethernet Cable connects Lowrance HDS units to other Lowrance Network Devices with Yellow Connectors.

SKU: NVX12730
Navico 25ft Ethernet Cable
The Lowrance 25ft Ethernet Cable connects Lowrance HDS units to other Lowrance Network Devices.

SKU: NVX12737
Navico 50ft Ethernet Cable
The Lowrance 50ft Ethernet Cable connects Lowrance HDS units to other Lowrance Network Devices.