![Ronstan Series 20 Ball Bearing Block – Swivel Hook Head [RF20180]](https://www.durablemarinebattery.com/wp-content/uploads/2026/08/ronstan-series-20-ball-bearing-block-swivel-hook-head-rf20180.webp)
Description
Series 20 Ball Bearing Block – Swivel Hook Head
Features:
- Low friction
- High static and dynamic load capacity
- Lightweight
- Low profile swivelling hook for quick and easy attachment
- Hook suits rope, stainless steel and webbing fixing points
- Precision molded Acetal sheaves running on stainless steel or Torlon® ball bearings provide high performance & low friction
Applications:
- Dinghy control lines
- Dinghy vangs
- Cunninghams
- Traveller controls
Materials:
- Stainless steel ball bearings
- UV Stabilized Acetal sheave
- Grade 316 stainless steel load strap and head fitting
- Impact and UV resistant, fiber reinforced Nylon cheeks
Specifications:
Sheave Ø:20mm(3/4″)
Max. Rope Ø:6mm(1/4″)
M.W.L.:135kg(300lbs)
B. L.:270kg(590lbs)
Weight:21g(0.7oz) View AllClose
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