Thank you so much !Briggs PN 698589.
Just Google the PN.
Just what you have is not one of the two optional filter bases. The OP has one of the optional bases. Now I don't know the screw size and threading but that's what I use my taps and dies for. It is however about 3/4" to 7/8" long.The screw is only needed if a cable attaches there. That mount is on many mowers where nothing is mounted to it. It is that way on our mower for 20 years now.
