![Ronstan Series 40 Ball Bearing Block - Single Upright Lead [RF40171]](https://cdn11.bigcommerce.com/s-tzjarqqxnb/images/stencil/1280x1280/products/10705/12834/70615XL__71473.1714538910.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-tzjarqqxnb/images/stencil/500x659/products/10705/12834/70615XL__71473.1714538910.jpg?c=1 "Ronstan Series 40 Ball Bearing Block - Single Upright Lead [RF40171]")
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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