Sony Electronics on Monday announced the pricing and availability of its super thin 4K Ultra HDTVs, X910C and X900C. The 75-inch X910C will be available for $5,499 while X900C will come in two sizes- a 55-inch model priced at $2,499 and a 65-inch model for $3,999. Both variants will be available starting next month, with presales starting from Monday.