Ultrasone Signature Pro S-Logic Plus Surround Sound Professional Closed-back Headphones with Hard-Sided Carrying Case The centerpiece of the handcrafted Signature Pro is a 40-millimeter titanium plated sound transducer developed in-house. Connectivity Technology: Wired Clear audio sound and detailed midrange and precise low-range frequency reproduction ensure rarely heard audio excellence. S-Logic Plus Technology; Dynamic principle, closed; Sound pressure level 98dB; 2 detachable cords with B-lock connections Hand made in Germany Signature Pro comes with a 5 year warranty This is an aftermarket of generic part