diff --git a/nixos/hosts/telchar/default.nix b/nixos/hosts/telchar/default.nix
index 52c51f6..a21885f 100644
--- a/nixos/hosts/telchar/default.nix
+++ b/nixos/hosts/telchar/default.nix
@@ -48,5 +48,6 @@
     system.motd.networkInterfaces = [ "wlp1s0" ];
     security._1password.enable = true;
     system.fingerprint-reader-on-laptop-lid.enable = true;
+    framework_wifi_swap.enable = true;
   };
 }
diff --git a/nixos/modules/nixos/system/default.nix b/nixos/modules/nixos/system/default.nix
index 82183ca..a3c5cf9 100644
--- a/nixos/modules/nixos/system/default.nix
+++ b/nixos/modules/nixos/system/default.nix
@@ -12,6 +12,7 @@
     ./security.nix
     ./systempackages.nix
     ./time.nix
+    ./wifi_swap
     ./zfs.nix
   ];
 }
diff --git a/nixos/modules/nixos/system/wifi_swap/default.nix b/nixos/modules/nixos/system/wifi_swap/default.nix
new file mode 100644
index 0000000..413a2d9
--- /dev/null
+++ b/nixos/modules/nixos/system/wifi_swap/default.nix
@@ -0,0 +1,50 @@
+# turns off the wifi when the usb device 0bda:8156 is connected.
+{ config, lib, pkgs, ... }:
+with lib;
+let
+  cfg = config.mySystem.framework_wifi_swap;
+  wifiSwap = pkgs.writeShellScriptBin "wifi_swap"
+    ''
+      #! /usr/bin/env bash
+      # This script turns off the wifi and on when the usb device 0bda:8156 is connected or removed.
+      # It is useful when you want to use a wired connection instead of wifi.
+      # The script is run by udev when the usb device is connected.
+      # The script is located at /run/current-system/sw/bin/wifi_swap
+      # The udev rule is located at <nix-store>-extra-udev-rules/etc/udev/rules.d/99-local.rules
+      # The udev rule is:
+      # ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="0bda", ATTR{idProduct}=="8156", RUN+="/run/current-system/sw/bin/wifi_swap"
+      # ACTION=="remove", SUBSYSTEM=="net", ENV{ID_USB_VENDOR_ID}=="0bda", ENV{ID_USB_MODEL_ID}=="8156", RUN+="/run/current-system/sw/bin/wifi_swap"
+      echo "wifi_swap ACTION: $ACTION" | systemd-cat -t wifi_swap
+      # Case or switch for $ACTION
+      case $ACTION in
+        add)
+          echo "Plugged in USB device 0bda:8156 (Realtek 2.5gbe). Turning Wi-Fi off." | systemd-cat -t wifi_swap
+          ${pkgs.networkmanager.outPath}/bin/nmcli radio wifi off
+          ;;
+        remove)
+          echo "unplugged in USB device 0bda:8156 (Realtek 2.5gbe) Turning Wi-Fi on." | systemd-cat -t wifi_swap
+          ${pkgs.networkmanager.outPath}/bin/nmcli radio wifi on
+          ;;
+        *)
+          echo "Uknown ACTION: $ACTION" | systemd-cat -t wifi_swap
+          ;;
+      esac
+    '';
+in
+{
+  options.mySystem.framework_wifi_swap = {
+    enable = mkEnableOption "framework_wifi_swap" // { default = false; };
+  };
+  config = mkIf cfg.enable {
+    # Create bash script and add it to nix store
+    environment.systemPackages = [
+      wifiSwap
+    ];
+
+    # Add udev rule to run script when usb device 0bda:8156 is connected or disconnected.
+    services.udev.extraRules = ''
+      ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="0bda", ATTR{idProduct}=="8156", RUN+="${wifiSwap.outPath}/bin/wifi_swap"
+      ACTION=="remove", SUBSYSTEM=="net", ENV{ID_USB_VENDOR_ID}=="0bda", ENV{ID_USB_MODEL_ID}=="8156", RUN+="${wifiSwap.outPath}/bin/wifi_swap"
+    '';
+  };
+}