Click to enlargeRonstan Low Friction Ring - 21mm Hole
Manufacturer: RonstanPart #: RF8090-21SKU: 55374
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Item #: 55374
Category: Hardware
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Description
Low Friction Ring - 21mm Hole Low Friction rings can be used as a lightweight alternative to a block in some applications. They are best suited for systems requiring relatively small line deflection angles, or for high static loads.
The design achieves a nicely rounded internal profile for smooth control line trim under load, and a deep external groove to retain the rope securely within the large shoulders when spliced into a loop. Features: Compact & lightweight Low friction Large shoulder secure allowing for rope lashing Durable Simple & reliable design Low maintenance
Specifications
| Brand | Ronstan |
|---|---|
| Part Number | RF8090-21 |
| EverTide SKU | 55374 |
| UPC | 9316800525966 |
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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