![Ronstan Series 40 Ball Bearing Block - Single Upright Lead [RF40171]](https://cdn11.bigcommerce.com/s-jxombk0idl/images/stencil/600x600/products/25967/40945/70615XL__57876.1697171282.jpg?c=1 "Ronstan Series 40 Ball Bearing Block - Single Upright Lead [RF40171]")
![Ronstan Series 40 Ball Bearing Block - Single Upright Lead [RF40171]](https://cdn11.bigcommerce.com/s-jxombk0idl/images/stencil/1280x1280/products/25967/40945/70615XL__57876.1697171282.jpg?c=1 "Ronstan Series 40 Ball Bearing Block - Single Upright Lead [RF40171]")
Product Overview
Series 40 Ball Bearing Block - Single Upright Lead
Lead blocks are a low profile solution for leading halyards or other rig sail controls back to cleats or jammers. Precision molded Acetal sheaves running on Acetal or Torlon® ball bearings provide high performance & low friction. The 2-stage ball bearing system provides consistent performance over the full load range.
Applications:
- Typically used for halyards at the mast base.
Materials:
- Acetal ball bearings
- UV stabilized Acetal sheave
- Grade 316 stainless steel load housing
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