# DockAccessory.Limits.Limit A description of a limit placed on an axis of rotation. ``` struct Limit ``` ## Overview Zero is the default minimum angular speed. Invalid limit specifications include minimum position greater than maximum position, minimum position equals maximum position, and maximum speed is less than zero. ## Topics ### Limiting speed and position [`let maximumSpeed: Double`](/documentation/DockKit/DockAccessory/Limits-swift.struct/Limit/maximumSpeed) The maximum speed that the dock accessory moves. [`let positionRange: Range`](/documentation/DockKit/DockAccessory/Limits-swift.struct/Limit/positionRange) The valid range that the dock accessory moves. ### Initializers [`init(positionRange: Range, maximumSpeed: Double) throws`](/documentation/DockKit/DockAccessory/Limits-swift.struct/Limit/init(positionRange:maximumSpeed:)) ## Relationships ### Conforms To [`SendableMetatype`](/documentation/Swift/SendableMetatype) [`Sendable`](/documentation/Swift/Sendable) --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)