Miller Adjustable Offset Upper Mast - 30 in. to 48 in.* This upper mast is designed to be part of a two piece DuraHoist mast system to increase the number of possible configurations for height restrictive applications. * The Miller Upper Offset Mast offers 30 to 489 inches of adjustment in a safety yellow powder coated package for increased durability. * This lightweight system breaks down without tools to create manageable components for easier storage, transport, and setup. ** All winch and block