With ultra-to medium-telephoto coverage, this versatile lens can be used in a wide variety of applications including landscape, snapshots and portraits. The tightly sealed, weather-resistant and dust-resistant construction enhances durability for use in both rainy and dusty conditions, making it a perfect companion for the weather-resistant PENTAX DSLR bodies. The SDM focus system incorporated in this lens results in a smoother, quieter autofocus operation using a built-in supersonic motor. Aspherical elements, extra low dispersion glass and PENTAX original lens coatings make this lens superior in contrast, clarity and edge-to edge sharpness.