利未记 15:9

וכל המרכב AND ANYTHING FOR RIDING — even though he has not sat upon it when riding, e. g. the hold in front of the saddle, which is called arcon in old French, becomes unclean as a part of something for riding on (משום מרכב), and the אוכף, saddle, which is called alves in old French, is unclean as being something to sit upon (משום מושב) (Eruvin 27a).

וְכׇל־הַמֶּרְכָּ֗ב אֲשֶׁ֨ר יִרְכַּ֥ב עָלָ֛יו הַזָּ֖ב יִטְמָֽא׃

And whatever saddle he that has the issue rides upon, shall be unclean.