New Delhi, Jan 12 (ANI): German headphones maker Sennheiser unveiled ultra-premium gaming headphones GSP 600. The state-of-the-art headphones focus hardcore gamers for their long duration of playtime. GSP 600 will go on sale by the end of January at an approximate cost of Rs. 16,000. The ergonomics of headphones suit hardcore gamers. All-new ear pad design of GSP 600 is made of ultra deep memory foam. Leatherette has been used in the headphones that has been claimed to resist sweat and provide cooling.