The Sennheiser CX 380 Sport II are noise-isolating ear-canal headphones featuring high-performance dynamic driver systems that deliver bass-driven stereo sound. The headphones come with three sizes of ear adapters which not only make them fit securely but also allow high passive attenuation of ambient noise. The CX 380 Sport II are sweat and water resistant and are washable under running water making it possible to use them during water activities. They are optimized for most portable media devices and come with a cable clip and carrying pouch. The CX 380 Sport II headphones stand out from other models in Sennheiser's Sport Line since they are ear-canal phones with a noise-isolating design while the other models in the Sport Line are earbud-style earphones so they are not designed to cancel out noise to the same extent as the CX 380s.