Genazym is auctioning the 15h century classic of Talmudic Methodolgy - הֲלִיכוֹת עוֹלָם, first complete edition (Constantinople 1510)

This methodological intro to the Talmud was held in high esteem, and R Yosef Karo wrote a commentary (סֵפֶר כְּלָלֵי הַגְּמָרָא) on it. One of the first Hebrew books ever printed

https://thechesedfund.com/rabbikatz/support-rabbi-katzz-podcast