Add some tropical vibes to your Boston Celtics game-day look with this Adventure Aloha Pattern 9SEVENTY Stretch-Snap Hat from New Era. The 9SEVENTY provides a modern adjustable fit and versatile style with its structured crown, semi-curved visor and performance stretch sweatband. COOLERA® technology wicks away sweat, while MICROERA™ technology acts as an anti-microbial to reduce odor, ensuring you stay fresh and comfortable all day long.