The lens features a focus mode switch as well as a zoom lock to prevent it from extending under its own weight. The zoom lock can also be released via zoom operation, ensuring the lock won't make you miss a shot.
A water- and oil-repellent coating on the front lens element makes it possible to shoot in harsh outdoor environments, while the dust- and splash-resistant construction keeps the internal elements protected.
Separate focusing elements work together to maintain focus throughout the entire zoom range.