Ronstan RF51500 50mm Fiddle Block | Series 50 Stainless Sailing Pulley

The Ronstan RF51500 is a compact and high-performance 50mm fiddle block, perfect for use in multi-purchase systems on dinghies, keelboats, and small yachts. Featuring a split sheave design, this block allows for precise line control in tight spaces where a traditional double block setup might not fit.

As part of the Ronstan Series 50, the RF51500 is built with a UV-stable acetal sheave and 316 stainless steel cheeks, providing strength, smooth operation, and excellent corrosion resistance. Ideal for vangs, cunninghams, outhauls, and trimming systems, this fiddle block helps reduce friction and increase mechanical advantage in your rigging.

✅ Key Features

• Ronstan RF51500 – 50mm fiddle pulley block

• Split sheave configuration for compact purchase systems

• UV-resistant acetal sheaves for smooth, low-friction line handling

• 316 stainless steel cheeks for corrosion resistance

• Ideal for vang, outhaul, cunningham, and trimming lines

• Lightweight, strong, and easy to install

• Medium-load rated for small to mid-sized boats

• Part of the Ronstan Series 50 sailing block range

Ronstan RF51500 50mm Fiddle block specifications:

• Sheave Diam. 55mm + 30mm
• Max. Rope Diam. 10mm
• Pin Diam. 3/16 in.
• Max. Working Load 750kg
• Breaking Load 1500kg