Biro Circle Ring LED ceiling light, DALI dimmable, diameter 60 cm Biro Circle Ring is an LED ceiling light with a high, ring-shaped lampshade made of aluminium with an opal white plastic cover, behind which LEDs are installed all around. The light with its rotationally symmetrical deep-wide light distribution and white cover emits direct, uniform downward light. It is equipped with a DALI dimmable ballast and is ideal for lighting offices, conference rooms and many other commercial areas - general colour rendering index CRI > 80 - service life L70/B50 at 25 °C: 276,000 h, service life L80/B20 at 25 °C: 153,000 h - housing material: aluminium / steel / plastic - permissible ambient temperature (ta): -20 °C - +25 °C - with electronic ballast, DALI dimmable