All Wool
noun
Something that is pure fur is pure fur... but what kind of fur? In this case it's wool, making this mean all wool.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
新しい純毛のセーター、チクチクして痒いんだよね。
My new all-wool sweater prickles and makes me itchy.