diff --git a/hosts/nonat/configuration.nix b/hosts/nonat/configuration.nix
index 272f083..aba0d9b 100644
--- a/hosts/nonat/configuration.nix
+++ b/hosts/nonat/configuration.nix
@@ -33,7 +33,9 @@
     externalInterface = "ens18";
     externalIP = (lib.head config.networking.interfaces.ens18.ipv4.addresses).address;
     internalInterfaces = [ "ens19" ];
-    internalIPs = "${ (lib.head config.networking.interfaces.ens18.ipv4.addresses).address}/${ (lib.head config.networking.interfaces.ens18.ipv4.addresses).prefixLength }";
+    internalIPs = [
+      (lib.head config.networking.interfaces.ens19.ipv4.addresses).address
+    ];
   };
 
   system.stateVersion = "21.03";