After a rule was proposed last year, it’s now been officially made a law: your drone needs to have its ID number visible on the outside. So, instead of just having it inside the device’s battery compartment, you’ll now have to put a “license plate” on your drone.

When the drone registration program was first launched in 2015, you were able to simply place the drone’s ID number inside the battery compartment. However, the FAA posted the new rule in an official document on Tuesday. It states that starting from 23 February 2019, drone owners will need to place the ID number on the outside of their aircraft and make it clearly visible. “Small unmanned aircraft owners are no longer permitted to enclose the FAA-issued registration number in a compartment,” FAA writes.

Apparently, FAA made this rule official following terror-related concerns expressed by FBI and Homeland Security. FAA explains that there is a risk of a concealed explosive device hidden inside the battery compartment, which could be activated when the drone is opened to find the registration number. FAA doesn’t give the details on how the “license plate” should look. All we know that the ID number needs to be “clearly visible.” So, if you already don’t have the ID number on the outside of your drone, you may want to add it. And if you still haven’t registered your drone, you can do it here. [via Digital Trends]