The pack of three Air Lens Gear from Redrock Micro adds lightweight precision gearing for accurate and repeatable focusing when using a follow focus or wireless remote (sold separately). The gears are small enough to leave on even when shooting stills. It is designed with lubricated nylon that wraps around your lens' focus ring. It features industry standard 0.8 gearing that works with any focus system, including the Redrock microFollowFocus, microRemote, and Eclipse.