just to let everyone know i am runnig the us carpet chassie i think its 3.5 mm then all the bulk head are machined down and the car is really good the only thing i had to do was get associated springs and bottom retainers for it but as for the hing pins you need the us spec . hing pin set i can post part numbers tommorw if you need them and my car is only a half ounce over wieght now with alum. bulk heads adn all the hop up on it