Click to enlargeRonstan Nylatron Sheave Box - Single Upright Lead Block
Manufacturer: RonstanPart #: RF453SKU: 55219
- 350 lb
- Stainless Steel
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Item #: 55219
Category: Blocks
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Description
Nylatron Sheave Box - Single Upright Lead Block Lead blocks are a low profile solution for leading halyards or other rig sail controls back to cleats or jammers. When mounted in an inverted position, are frequently used as upright leads.
Features: The external tabs can be formed to fit the spar profile before fastening Applications: Typically used in dinghy spars for control lines such as outhauls Materials: Nylatron® sheave Grade 316 stainless steel load housing Specifications: Sheave Ø: 22mm(7/8") Max. Rope Ø: 3mm(1/8") Max.
Cable Ø: 3mm(1/8") Fastener Ø: 5mm(3/16") M. W.
L. : 160kg(350lbs) B.
L. : 350kg(700lbs) Weight: 30g(1.
1oz)
Specifications
| Brand | Ronstan |
|---|---|
| Part Number | RF453 |
| EverTide SKU | 55219 |
| UPC | 9316800000425 |
| Material | Stainless Steel |
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 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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