Harken 312 25mm High Strength Wire Block. Wire blocks are lightweight, low friction blocks designed to carry wire halyards and control lines on boats of all sizes. This block uses low-friction thrust washers and stainless steel sideplates which give superb chafe resistance.

• Sheave diameter: 25mm
• Weight: 35g
• Maximum wire diameter: 2mm
• Maximum line diameter: 4mm
• Maximum working load: 454kg
• Breaking load: 907kg