Made to deliver a striking 3D illusion, Happy Socks Filled Optic Combed Cotton Socks are ready to add some colour and eye-catching impact to your wardrobe choices, The \’filled\’ optic pattern (as opposed to a wire frame style outline) increases the contrast for the most intense 3D effect, with blocks appearing to advance and recede. Liven up your corporate or casual wear with these dynamic socks. Happy Socks Filled Optic Combed Cotton Socks are Swedish-designed, made from a quality, combed cotton rich blend for comfort and wear resistance.