These lenses narrow the beam of MaxLite HLV high bays from 90°x90° to 45°x90°. They are a great choice for spaces with aisles or racking, focusing light downward to better illuminate shelf fronts and labels. A lens swap can be completed in seconds without any tools thanks to the fixture's easy-swap design. This pack is sized for the HLV-135W models and includes two lenses, enough for one fixture.