The C0 label designates a specific category of drones under European legislation, which applies to unmanned aircraft with a maximum take-off mass of up to 250 grams. The maximum take-off mass, often referred to by the acronym MTOM (Maximum Take-Off Mass), includes not only the drone itself but also the battery and any additional equipment, such as a camera. For drones in this class, their operation falls under the so-called "open" A1 category, which has the most lenient rules. A pilot with such a drone may fly even over uninvolved persons, but it is forbidden to fly over gatherings of people. A pilot certificate is not required to operate a C0 drone; however, the pilot must be familiar with the manufacturer's user manual. If the drone is equipped with a camera or other sensor capable of recording personal data, registration of the drone operator is necessary, not of the machine itself. Furthermore, the drone must be structurally safe, must not have sharp edges, and its maximum speed is limited to 19 m/s.
