SwissStar AL3 • Top thermal insulation • Top design • Top quality Aluminum – a fantastic material for windows and doors. But in an age of rising energy costs, preference is given to wooden and plastic windows. The reason for this is the high Uf values of existing aluminum window systems (1.7 to 2.2 W / m²K). SwissStar AL3 windows with concealed fittings have a Uw value of 0.698 to 1.003 W / m²K. This means the windows offer a persuasive choice when it comes to thermal insulation and display all the benefits of aluminum in full. A hollow chamber polyamide profile is made from the profile webs and finished off using the patented snap connection.