$65 Helly Hansen Koster Board Shorts Swim Trunks Striped Marine Size 33 The $65 Helly Hansen Koster Board Shorts Swim Trunks in Size 33 feature a stylish striped marine design in blue color. Made of 100% polyester material, these swim shorts are perfect for various water activities such as training, water polo, lifeguarding, surfing, and recreational purposes. With a logo theme and lined feature, these swim trunks by Helly Hansen are a high-quality and durable choice for men's swimwear.