EarTech Music Quad Driver Custom Molded In Ear Musician Monitors Headphones Pair of Quad Driver custom in-ear musician monitors packaged with a detachable cable (50 or 64 inch), protective storage case, DryCaddy DiscTM desiccant, shirt clip, cable organizer, 1/4" adaptor, & ear wax removal tool. Frequency Response is 12Hz-18kHz, Impedance is 12Ohms, Sensitivity is 112dB SPL/mW@1kHz, Noise Isolation is -26dB Balanced armature drivers, Passive tuning network, 26 dB ambient noise reduction, Hypoallergenic and hard acrylic shells Ear impressions are required with all custom products. We recommend a trained hearing healthcare professional in order to get the best impression and fit! Especially popular with bass players and drummers, the Quad is a dynamic combination of power and clarity.