Decora Paddle Switch Guard

I have a lot of three way switches in my house and as I add smart switches, which require constant power, I have to disable the other side of the three way switch (or spend a lot of money swapping them out). This guard mounts to either the top or bottom screw for a decora paddle switch plate and prevents someone from inadvertently flipping the switch on (which would remove power from the downstream smart switch). This switch guard would also work well for a smart bulb application, which also a