Ronstan RF20202 Double Ball Bearing Pulley 20mm – Series 20 Block

The Ronstan RF20202 Double Ball Bearing Pulley (20mm) is a compact, high-performance Series 20 block designed for efficient control line systems on modern sailing boats.

Featuring twin 20mm acetal sheaves running on precision stainless steel ball bearings, this block delivers exceptionally low friction and smooth operation, making it ideal for dynamic sailing applications such as vangs, cunningham systems, and traveller controls.

The RF20202 includes a 2-axis shackle head, allowing the block to be aligned at 0° or 90°, ensuring optimal load direction and reducing friction and wear on your rigging system.

Constructed from UV-stabilised acetal sheaves, fibre-reinforced nylon cheeks, and 316 stainless steel load components, this block offers excellent durability and corrosion resistance for long-term use in harsh marine environments.

With a maximum working load of 350kg and breaking load of 700kg, the RF20202 delivers impressive strength in a lightweight, compact design—perfect for dinghies, skiffs, and small keelboats.

Key Features

• Double 20mm sheaves – efficient load distribution
• Ball bearing system – ultra-low friction and smooth operation
• 2-axis shackle head – adjustable alignment (0° or 90°)
• High load capacity (350kg MWL / 700kg BL)
• Lightweight (~42g)
• Durable composite construction – UV and corrosion resistant
• Compact design – ideal for tight rigging setups

Specifications

• Brand: Ronstan
• Model: RF20202
• Series: 20 Ball Bearing
• Product Type: Double pulley block
• Sheave Diameter: 20mm
• Max Rope Diameter: 6mm
• Pin Diameter: 4.0mm
• Maximum Working Load: 350kg
• Breaking Load: 700kg
• Weight: ~42g
• Materials:
  • UV-stabilised acetal sheaves
  • Stainless steel ball bearings
  • 316 stainless steel load strap
  • Fibre-reinforced nylon cheeks

Ideal Applications

• Vang systems
• Cunningham and outhaul controls
• Traveller systems
• Dinghy and skiff rigging
• General-purpose control lines

This block is ideal when you need efficient load handling and smooth operation in a compact, lightweight form.

Why Buy from Barton Marine NZ?

• Trusted NZ Ronstan supplier
• Fast nationwide delivery
• Genuine high-performance sailing hardware
• Ideal for NZ racing and cruising conditions

Pro Tip 

• Align the block using the 2-axis head to minimise friction
• Ideal for tight rigging layouts where space is limited
• Pair with low-stretch Dyneema lines for best performance