Is it a big cockup?

[Johnny31]

So I finally found some time to do my rear pads and discs... It all went smoothly, bar the bolts on the caliper brackets. The space is incredibly tight in the rear! So I could neither use the breaker bar nor the torque wrench afterwards... :(
Nonetheless, my problem is elsewhere: I was on the full autopilot and (as I did with the fronts) just replaced everything that was provided with my new ATE pads and discs.
Only when the car was back on its "feet", I realised something rather interesting: the caliper holding bolts in the kit were both the same, normal size. However, what I removed from the car looks like the attached.
On both sides, it appears that there is a big balancing weight attached to the upper one.
So, my question is: what is the purpose of this and do I need to source the same ones? #puzzled (http://www.vwaudiforum.co.uk/forum/usertag.php?do=list&action=hash&hash=puzzled)
https://uploads.tapatalk-cdn.com/20180830/bfbfd7be3a5b72f5ec3cd1f935566a70.jpg

Sent from my mobile...

[Rob69]

It's a low frequency vibration damper, meant to reduce rattles, groans and moans. I'm not sure how effective these actually are, doubt you'll notice any difference without it, we seemed to manage for years with just the plain bolts. I've come across a Vauxhall using something similar

[morski]

The RS6 has 2 each on the fronts. Just not sure exactly how effective they are as the RS brakes are known to howl anyway

[Rob69]

I dare say if you wanted to refit the damper it would be ok to reuse the bolt as they are not torqued to yield and a drop of low strength threadlocker like loctite 222 would keep it in place.