Yarn amount is sufficient to make 4-5 Cozies.
About 3-1/2"x9-1/2" (9 x 24 cm), to fit a standard coffee or tea mug
12 half double crochet + 10 rows = about 4" (10 cm).
BE SURE TO CHECK YOUR GAUGE.
Row 1: Half double crochet in 3rd chain from hook and in each chain across.
Row 2: Chain 2, turn. Half double crochet in each stitch across - 29 stitches at the end of this row.
Repeat Row 2 until piece measures about 3-1/2" (9 cm).
Sew short sides of Cozy together for about 1/2" (1.5 cm) at top and at bottom, leaving remaining 2-1/2" (6.5 cm) open for mug handle.
With sewing needle and thread, sew button, centered, onto one edge of handle opening. Use spaces between stitches as buttonhole.