The beam angle is advertised as being 6°, but in reality measures around 10-11°. At a distance of 4 m the beam has a diameter of almost 80cm.
I therefore had to return the product, because the beam angle was too wide for lighting my mirror ball.
Furthermore, the reflections of the light from a mirror ball onto the wall, appear like little rings. Somehow the reflector in this light does not make a perfect beam. The ring shape is not visible when shining directly onto a wall, but it is also not visible when shining onto the mirrorball with a different light, so it is caused by this spotlight and not by the mirrorball.
The device itself is sturdy, well made and measures around 8 cm with a diameter of 7 cm, without the mount.
I wish a simple spot would be made with an adjustable beam angle, where you can move the reflector a bit by turning the head, like some flashlights have. That would make a very versatile pin spot.