From the manufacturer:
Never one to cease evolving, Sennheiser has improved upon the highly regarded CX 980 with the brand new CX 985. Featuring a real metal alloy housing and Sennheiser's impeccable miniature dynamic transducers, the CX 985 sounds as good as it feels in the hand.
The dynamic transducer has been re-tuned for absolute precision audio; effortless bass, realistic mid-range and soaring treble response without sounding unnatural or harsh. It gets better with ultra-low total harmonic distortion which delivers the source audio and nothing else.
A redesigned audio plug works for you with a completely unique variable array: choose a straight configuration or use it at a 90 degree angle to minimize strain on your audio player's jack plug. The ergonomics do not stop there thanks to an ultra-rugged "Y" style cable that is tangle-resistant and reduces weight and can be anchored to the user's clothing with the included cable clip. A bulit-in volume control keeps your tunes at your fingertips.
– More balanced sound quality over its predecessor the CX 980
– Aggressive noise isolation means you can listen at safer levels without sacrificing detail
– Swiveling plug lets use it in a straight pin or right-angled configuration
– Fit kit lets you dial in the perfect fit for optimum frequency response and noise isolation; a 2nd set with enhanced bass is included
– Real metal construction; strong, durable, classic
– Storage pouch keeps your earphones safe during storage/transport
– Cable clip anchors the cable to your clothing for a seamless fit
– Included airline adapter lets you plug in at a safe volume level