Click to enlargeRonstan Series 30 Ball Bearing Block - Single - Loop Top
Manufacturer: RonstanPart #: RF30101SKU: 55171
- 660 lb
- Nylon
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Item #: 55171
Category: Blocks
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Description
Series 30 Ball Bearing Block - Single - Loop Top Features: Low friction 2-stage ball bearing system provides consistent performance over the full working load range High static and dynamic load capacity Light weight Versatile head fittings Sheaves running on Acetal or Torlon® ball bearings provide high performance & low friction Can be fitted with a shackle in either of two planes to allow correct alignment of the block Applications: Primary lead blocks on dinghies and catamarans Control lines on larger yachts Materials: U. V.
stabilized Acetal sheaves Acetal ball bearings Impact modified, fiber reinforced and U. V.
stabilized Nylon cheeks Grade 316 stainless steel load straps and head fittings Specifications: Sheave Ø: 30mm(1-3/16") Max. Rope Ø: 8mm(5/16") M.
W. L.
: 300kg(660lbs) B. L.
: 750kg(1,650lbs) Weight: 28g(1. 0oz)
Specifications
| Brand | Ronstan |
|---|---|
| Part Number | RF30101 |
| EverTide SKU | 55171 |
| UPC | 9316800258260 |
| Material | Nylon |
Specifications are provided by the manufacturer. Confirm fitment for your application before ordering, or contact us and we'll help.
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Returns & warranty
Returns are accepted within 30 dayson items that are unused and in their original packaging. Some items may be subject to a manufacturer restocking fee. Special-order items may not be eligible — if you're unsure, ask us before ordering.
Ronstan productscarry the manufacturer's standard warranty. For a warranty claim or a return authorization, see our full returns policy or contact us.
Sailing — frequently asked
- How do I size a block for my sailboat?
- Match the block to the line diameter it will carry and to the working and breaking loads of the system (sheet, halyard, control line). Makers publish load ratings and line-size ranges — choose a block whose working load comfortably exceeds the real-world load, without going so large it adds needless weight.
- What is running rigging?
- Running rigging is the moving lines that control the sails — sheets, halyards, and control lines — as opposed to standing rigging (the fixed wire that holds up the mast). Running rigging should be matched to the boat’s blocks, clutches, and winches for smooth, reliable sail handling.
- How do I maintain sailboat winches and hardware?
- Rinse with fresh water after sailing, keep sheaves and bearings clean, and periodically service winches (disassemble, clean, and re-grease per the maker’s instructions). Marine-grade stainless and good maintenance keep hardware working smoothly when loads are high and timing matters.
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