Aperture can manually adjusted according to the light level available, also can be fixed and locked for more convenience. | You can change the shooting range by changing the focal length, very useful for composition. | With low distortion, high compatibility, can adapt to most security cameras. | The zoom lens can be used as multiple fixed lenses, thus saving time when changing lenses when traveling. | Lens adopts aluminium alloy body and high quality lens, sturdy, durable and has long service life.