whats up with my pipes?

[swepzz]

hi. the pipes that were on my bike when i got it has bolts holding the expansion chambers together. i tried looking around some and i guess they're adjustable? whats up with this? i was thinking about tightening and loosening the bolts to see what happens but am wondering if anyone else is familiar with this?

[Snopczynski]

They are probably lrd adjustables.

[Boosted GMC]

I have a buddy with a set of those lrd adjustable pipes with a stallworth port job. We played with them you can feel a slight difference between all the way in and all the way out.