The RG-316SNF is the adapter cable for connection between indoor AP and RG213 cable. The cable has a male reversed SMA connector on one side to connect with AP and female N-Type connector on the other side to connect with RG213 cable (or any outdoor cable). A connector typically has 0.3 dBi of signal loss, the combined signal loss of the 2 connectors and 30cm cable is about 1dBi. This cable will use in conjunction with RG-213NN for extended connection between a indoor AP and a outdoor antenna.