diff --git a/env.example b/env.example
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+# Copy this file to .env and change all the values.
+
+# Router address
+SIPREVERTER_HGU_ENDPOINT=http://192.168.1.1
+# Router password
+SIPREVERTER_HGU_PASSWORD=change_me
+
+# The following options are the ones which the program should overwrite when
+# they are changed.
+
+# Outbound proxy address
+SIPREVERTER_CONF_ADDRESS=change_me
+# Outbound proxy port
+SIPREVERTER_CONF_PORT=change_me
+# SIP server interface
+SIPREVERTER_CONF_INTERFACE=change_me