![Ronstan Series 40 Ball Bearing Block - Double - Swivel Head [RF40200]](https://www.bestmarinebattery.com/wp-content/uploads/2026/08/ronstan-series-40-ball-bearing-block-double-swivel-head-rf40200.webp)
Description
Series 40 Ball Bearing Block – Double – Swivel Head
Features:
- Low friction Acetal or Torlon® bearing system
- Lightweight
- Cheek cut-outs for easy bearing maintenance
- Features a swivel shackle head for full 360° rotation
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:
- Mainsheet
- Halyard
- Vang
- Spinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8m (26ft)
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