A very good air/fuel ratio adjustment kit for an Edelbrock 750 cfm carburetor. Parts are very easy to replace, even if the carburettor is still on the car. I use a broadband lambda sensor to tune cars and the tie rods, injectors and springs are very closely matched to the carburetor manuals. It was a life saver to completely change the way my modified 406 sbc works as a daily driver and also occasionally on the road.