Sennheiser MX65 Twist to fit Earbuds with Built-In Basswind Stereo System (Discontinued by Manufacturer) Innovative holding system (Twist-to-fit system) ensures best possible fit Sennheiser Basswind system plus delivers an extremely powerful bass response Includes an ear adapter set with rubber pads to personalise the size of earbuds Optomised for MP3, iPod,iPhone, CD players and portable gaming systems Symmetrical cable