To maintain a high lumen output, high amount of heat is to be expected. During normal use, temperature of the area around the lens is expected to go up to 75C degrees. In cases where heat dissipation is affected, throttle threshold is set to be 90C, at which point the light output will drop immediately to make sure no damage to internal components can occur. This is more so the case for higher output lights. We designed them so that under ideal conditions, with adequate airflow, such as riding moderate to high speeds, the heat can be dissipated fast enough so that the advertised max output can be maintained consistently.
The PC material we use for the optical lens has a 130C degree max allowance before deformity could potentially occur, melting point is much higher. In any case please refrain from turning on the light with the front lens and/or its surrounding metallic shell covered up, such as turning the light on in your pocket, as heat build up in this instance could be extremely fast. For an instant it may push the temperature past the melting limit.
