Scope Bracket Thumb Screw Thread

I downloaded the drawings but can´t make out the thumb screw thread size. I need it, as I´ll have to supply my German gunsmith with a tap when he mounts the bracket. Can anyone provide me with the correct thread?

1/4'' bsf

1/4" x 26 BSF

Thanks for the help. I´ll order the tap, as I don´t expect a local gunsmith´ll have anything other than DIN.

(Just a thought .... what would I do here in Mauserland without Milsurps?)