Nikon NIKKOR Z 600mm f/6.3 VR S Reference Manual page 6

CAUTION
Do not leave the lens pointed at the sun or other strong light sources.
Light focused by the lens could cause fire or damage to product's internal parts.
When shooting backlit subjects, keep the sun well out of the frame. Sunlight
focused into the camera when the sun is close to the frame could cause fire.
Do not leave the product where it will be exposed to extremely high
temperatures for an extended period, such as in an enclosed automobile
or in direct sunlight.
Failure to observe this precaution could result in fire or product malfunction.
Do not transport cameras or lenses with tripods or similar accessories
attached.
Failure to observe this precaution could result in injury or product malfunction.
6 For Your Safety