Marc Ecko Unltd EKU-BLT-BK Bolt Inner Ear Earphones (Black) (Discontinued by Manufacturer) Noise-reduction stereo earphones with Mega bass iPod and iPhone compatible 10mm speaker diameter Frequency response: 18Hz-20kHz Includes satin carry bag and 3 sizes of silicone gel caps iPod/iPhone Compatible 3 Silicone Gel Caps and Satin Carry Bag Included 10 mm speaker 16 OHMS Impendance 3.5mm Plug and 1.3M cable