NG double head Outdoor RJ45 LAN Connector Ethernet Network Cable Extension coupler Adapter waterproof Female to FemaleUsed  to connect two RJ45 cables together, Make two RJ45 cables work as one cable. 8 Conductors w/ Gold-plated  contactsWaterproof IP67 Its great for use  in marine, warehouse, or any wet environment. It also has potting inside  of it to prevent any water intrusion in case the cable breaks or  someone forgets to put the seal-cap back on.