From the North American Schachenmayr website:
Always wanted to knit a neon-colored accessory, but don´t want it to be too flashy? Then why not make this hat? The two-colored rib pattern in denim-grey and neon yellow (Schachenmayr original Boston) looks super – cheeky, clever and young-looking!

Finished dimensions:
Completed hat fits a head circumference of 20½ to 22 inches (52 to 56 cm) and measures approximately 9¾ inches (25 cm) tall.

Yarn Information:
A - 00190 grey denim
2 skeins
120 yards

B - 00121 neon yellow
1 skein
60 yards