Lightweight, low-friction wire blocks carry wire halyards and high-strength control lines on boats of all sizes. High-load composite bearings carry axial loads. Hardkote-anodized Teflon impregnated sheave for strength and corrosion resistance.25 mm (1.00 in) wire blocks use low-friction thrust washers. 38 mm (1.50 in) and 51 mm (2.00 in) wire blocks feature side load balls between the sheave and the side plate to minimize friction from unfair leads. Use for: Wire halyards, Vangs and Control lines.