HARKEN 51 mm Wire High Strength Thru-Deck Block, 310 Sailboat Blocks & Hardware_51 mm Wire High Strength Block Sheaves feature sleeve bearings to

Sheaves feature sleeve bearings to handle high static loads and are ideal for halyards or limited purchase systems on cruising boats

ESP blocks feature sleeve bearings to ensure smooth

The larger sheave is compatible with a 9/16" line

and condition the bearing surfaces

Harken 51mm High-Strength Cheek Block with high-load composite bearings to carry axial loads

HARKEN 51 mm Wire High Strength Thru-Deck Block, 310 Sailboat Blocks & Hardware_51 mm Wire High Strength Block Sheaves feature sleeve bearings toHarken 51mm Thru Deck High Strength Block allows lines through the deck and bulkhead. Harken's Lightweight, low friction blocks with high load composite bearings carry wire halyards and control line cascades. Side load balls reduce friction from twists or unfair leads on 304 311. 300 303 has thrust washers. Blocks open to allow passage of swaged wire. Hard Lube anodized sheave for strength and corrosion resistance. Cheek blocks include fasteners.