Lewmar is focused on making the lives of boaters easier. Our 90 mm synchro block, is designed for mainsheet and vang systems, halyards, halyard tuning systems and masthead blocks. Lewmar's innovative engineering has produced a replacement synchro block that performs to ball and roller blocks used in racing.The free spin bearing handles higher static loads, namely mainsheets and boom vangs, masthead blocks, halyard tuning systems and halyards. The larger sheave diameter minimizes rope friction. This is synchronized with running rigging systems and is the ideal choice for sailors and allows an easy and smooth transfer of power from deck to sail.Lewmar, a renowned maker of luxury marine equipment, builds winches, hatches, port lights, glass and glazing products. The company is a proud member of the Lippert family, which produces highly engineered products for the RV, marine, automotive, commercial vehicle and building industries. Lippert's commitment to its customers is always moving forward: always making their experience better.Lewmar, a well-known name among boaters and boatbuilders across the globe, is the world's premier leisure marine equipment supplier, designs, manufacturers winches, hardware, hatches, anchoring and windlass products. Lewmar is proud member of Lippert, a leading, global manufacturer and supplier of products for the RV, marine, automotive, commercial vehicle, and building products industries. Lipper's commitment to their customers-always moving forward. Always making your outdoor experience, whether it is on land or water.TRUSTED BRAND - Unmatched quality, engineering excellence and high-performing boating products since 1946. EASY TO USE - Practical switch from swivelling to fixed shackle. INNOVATIVE DESIGN - Featuring a "tool-free" sliding swivel locking mechanism. HIGHLY ENGINEERED - built with stiff glass reinforced cheeks to prevent lines from wedging. DURABILITY - Stainless steel strap for improved strength and proven life extention.Date First Available: February 7, 2020. Best Sellers Rank: #363,837 in Sports & Outdoors. Customer Reviews: 5.0 out of 5 stars 1 rating 5.0 out of 5 stars. : B00XCIW8LG. Manufacturer Part Number: ?29929001BK. Exterior: ?Machined. Is Discontinued By Manufacturer: ?No. Item model number: ?29929001BK. Package Dimensions: ?7.8 x 5 x 1.65 inches. Item Weight: ?1.08 pounds. Model: ?29929001BK. Brand: ?Lewmar. Manufacturer: ?Lewmar.