Personalized Underestimate Old Man Longboard Adult Sweatshirt. Funny retired surfer Adult Sweatshirt - White with surfboard. Never Underestimate An Old Man On A Longboard. Great gag birthday or retirement gift. Stay warm and stylish with this classic adult sweatshirt, perfect for everyday comfort. Crafted from soft, durable fabric, it features a relaxed fit for added coziness. Whether you’re lounging at home, running errands, or enjoying outdoor activities, this versatile sweatshirt is a wardrobe essential for any season.