Is there a shiur for the item the soldier is obligated to carry in Devarim 23:14?
וְיָתֵד תִּהְיֶה לְךָ עַל אֲזֵנֶךָ וְהָיָה בְּשִׁבְתְּךָ חוּץ וְחָפַרְתָּה בָהּ וְשַׁבְתָּ וְכִסִּיתָ אֶת צֵאָתֶךָ
And you shall keep a stake in addition to your weapons; and it shall be, when you sit down outside [to relieve yourself], you shall dig with it, and you shall return and cover your excrement.
That is, what types of items qualify for this mitzvah, and what size must they be?