Sony Lightweight Water-Resistant Sweat-Proof Active Series Sport Headphones (Green) 9mm Drivers - Sony headphones deliver dependable, quality audio reproduction time after time. Equipped with 9 mm high-sensitivity driver units Water-Resistant, Sweat-Proof Design - The water resistant housing prevents sweat and water from leaking in, making these headphones ideal for an active lifestyle Adjustable Ear Loops - Easily adjust for a precise fit by looping the ear loop around the ear and pulling snug. Once in place, the sport earbuds stay put, letting you focus on matters at hand Includes 4 Pairs of Hybrid Ear Pieces - Supplied hybrid silicone earbuds, in 4 sizes, allow for a tailored fit that maximizes overall sound quality and comfort The 3.9-foot long cable is serrated to help reduce tangles, and the included clip and cable length adjuster help keep it comfortably placed while exercising