High quality blocks that have evolved from years of experience. The 60mm double with becket is great for boom vangs, backstay systems, mainsheet systems and other applications that require a 4:1 purchase. The larger sheave is compatible with 1/2" line.The HTX line is Lewmars answer to the racer/cruiser looking for a top quality block with racing type performance without having to pay a Grand Prix price. A collaboration with boat builders and sailors blended with years of manufacturing experience with have resulted in strong, efficient blocks made to handle high loads of todays smaller diameter lines. Aluminum cheeks add strength and rigidity to the block and serve as an excellent foundation for a combination of plain and ball bearings. The center plain bearing provides efficiency for high loads while Delrin ball bearings handle the side thrust loads. Safe working loads and maximum line diameter is clearly marked on the edge of the durable and UV resistant acetal sheave. The head pin design comes from a page out of Lewmars racing book. The stainless steel pin swivels freely, but can be locked in one position with a grub screw locking mechanism similar to those found on racing blocks. Included shackles are 316 stainless steel for superior corrosion resistance. It takes high quality materials, the knowledge of sailors and builders, and race proven design to produce a block of this caliber at a racer/cruiser price point. Key Features Reliable, quality block designed for racer/cruiser applications Engineered for high loads and reduced diameter lines Aluminum cheeks add strength and rigidity Plain central bearing handles high loads with efficiency Delrin (acetal) ball bearings control side loads Head pin design based on racing level blocks Grub screw locking mechanism secures blocks in a fixed position Acetal sheave features clearly labeled safe working load and maximum line diameter Ideal for frequently adjusted loads Compatible with 1/2" line Ideal for: Boom vangs Backstay systems Halyard tuning systems Other 4:1 systems Selection GuideSheave DiameterCompatible LineHead