K&M 24471 Speaker Wall Mount Black

I purchased the 24471 for my almost 10 kg per piece Focal Alpha 80 Evos. The 24471s are rock-solid on the brick wall they got mounted on, since there's space enough between the four screws, but the angle indication is not much of help... You see, when holding the speakers up, while tightening the screws and then release the speakers, the angle stated before changes afterwards. A lot better to use external tools for this, or even your eyes.