Re: 70-71 merc 650 throttle/shifter control bolts
The thread size is 3/8",the thread pitch = number of turns per inch (16) and the 1" = length of the bolt.More often than not a given bolt size will have a standard thread pitch depending on whether it is a fine thread or a course thread bolt so that it will not be difficult to find a new one.Other parameters involve hardness and the type of material the bolt is made of among other things.Ron Gordon