The Harken 29 mm Zircon Block — Becket, Part No. 2186, can handle a maximum working load of 80 kg (175 lb). It is designed for use with lines up to 6 mm (1/4 in) in diameter and has a sheave diameter of 29 mm (1 1/8 in). With six new models added to the Zircon line, there are now eighteen options to choose from. While no block is suitable for all purposes, Zircon excels in control lines requiring a multi-part purchase system. Its quick responsiveness allows for easy adjustments, making it ideal for maneuvers such as releasing a Cunningham or adjusting the jib lead for added power in choppy conditions.