The Royal Invert range is designed to prevent that hang up you get whilst grinding on a lot of trucks. By inverting the kingpin it is also reported to ge=ive greater turning ability making all those tight angle grinds a bit easier.
5.25" or 5.5"
Royal Inverted Kingpin Trucks(Pair)
If you would like to alter the tension in your turn, please do so by tighting the king pin. To be accurate, this should be done in very small increments so as not to over-tighten causing the bushings to bulge. If you do ride them whilst they bulge you could wear them out fast or worse cause a split which could be dangerous. Be careful when adjusting your kit and stick to basic safety guidelines.