What do rigid Collar do?
Bolt holes through the chassis panel and sub frame are normally too big as they were designed for ease of production in the factory.
When the car leaves the factory, everything is new and tight and the chassis hardly moves. After a while, the bolts become slightly looser and movement between the panels begins.
This is why an older vehicle fitted with new bushes, Shocks and springs, still doesn’t behave like a new car.
Rigid Collars are aluminium sleeves that fit between the moving panels and with a properly sized bolt (and Bolt Hole as part of the Rigid Collar) is crushed into place when tightened, joining the two panels and stopping movement forever.