diff --git a/contrib/99-tillitis.rules b/contrib/99-tillitis.rules
index e07672c..36ce90a 100644
--- a/contrib/99-tillitis.rules
+++ b/contrib/99-tillitis.rules
@@ -1,6 +1,5 @@
 # CH552 bootloader (for unprogrammed CH552 chips)
-SUBSYSTEM=="usb", ENV{DEVTYPE}=="usb_device", ATTR{idVendor}=="4348", ATTR{idProduct}=="55e0", MODE="0666", GROUP="dialout"
+SUBSYSTEM=="usb", ENV{DEVTYPE}=="usb_device", ATTR{idVendor}=="4348", ATTR{idProduct}=="55e0", MODE="0660", GROUP="dialout"
 
 # TP-1 programmer (USB mode)
-SUBSYSTEM=="usb", ENV{DEVTYPE}=="usb_device", ATTR{idVendor}=="CAFE", ATTR{idProduct}=="4010", MODE="0666", GROUP="dialout"
-
+SUBSYSTEM=="usb", ENV{DEVTYPE}=="usb_device", ATTR{idVendor}=="cafe", ATTR{idProduct}=="4010", MODE="0660", GROUP="dialout"