Viewing the Sun through light-concentrating optics such as binoculars is hazardous without an attenuating filter to dim the sunlight. Suitable filters are available at welding supply shops and camera stores. Viewing the Sun through unfiltered 7x50mm binoculars can deliver as much as 2.5 watts of sunlight into each eye, over 300 times more power than naked eye viewing. Even brief glances at the Sun through binoculars can cause permanent blindness.