Force (Prestolite) Engine rectifier. (typical for Force Outboards or the Force outdrive units) Suitable for the Force series engine (50hp-150hp) in the late 80's and early 90's with the (blue) Prestolite Ignition systems Increasingly harder (and more expensive) to come by so it is always a good idea to have a spare if you need it, very cheap insurance mid-summer.. -Rectifier: $25