Where does “[[rucznica]], [[rusznica]]” come from?

[[rucznica]], [[rusznica]] (Old Polish) comes from Czech ručnice, from Czech ruční, from Czech ruka, from Old Czech ruka, from Proto-Slavic rǫka, from Proto-Balto-Slavic ránkāˀ, from Proto-Indo-European wrenk-, from Latvian wer- — to turn, to bend.