Painful.
It can be not arm or sled, but just connector pin. It can either break or just not properly fixed, just drop out.
They say the limit weight is of 3.5kg. An Arri has to be several times heavier.
Arms (by behavior) look like it can hold it good. And point where it broke is at the connection of sled and arm.
So, most probably arm was adapted but pin used was inappropriate or fixing of it was improper for this weight.
"His arm is actually a great invention. FYI my pro ball links have failed twice in the same way. One in my back mounted best while walking upstairs and the other in and ATV in off road conditions. So this happens even to the best arms. It wasn't the socket block. It was the ball links and even though they where German they failed the high frequency vibration test." Gustav Penna
Sounds weird. What is this "pro ball links"?
Only ball like things in arm are near vest and it can cause fall only if outside part will break completely apart.
This has nothing to do with strange "vibration test".
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