Happymodel Crux35 is a small frame for building a drone that can hold up to 3.5" propellers. The frame's light weight of 26 grams makes it possible to build a small racing drone or ultralight with long battery life. The diagonal distance of the motors is 150mm. The frame can accommodate both 20x20mm and 25.5x25.5mm M2 mounting hole plates, nano(14mm) size cameras and 9mm M2 mounting hole motors.