diff --git a/roles/usb/files/50-usb.rules b/roles/usb/files/50-usb.rules
index 75a5a83..13540a8 100644
--- a/roles/usb/files/50-usb.rules
+++ b/roles/usb/files/50-usb.rules
@@ -1 +1 @@
-KERNEL=="ttyACM[0-9]*", SUBSYSTEM=="tty", ATTRS{idVendor}=="0658", ATTRS{idProduct}=="0200", MODE:="0666"
+KERNEL=="ttyACM[0-9]*", SUBSYSTEM=="tty", ATTRS{idVendor}=="0658", ATTRS{idProduct}=="0200", MODE:="0777"