Click to enlargeRonstan Series 50 All Purpose Block - Triple
Manufacturer: RonstanPart #: RF51300SKU: 70685
- 33 ft
- 90°
- Stainless Steel
Item #: 70685
Category: Blocks
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Description
Series 50 All Purpose Block - Triple Features: Exceptionally high working loads Low maintenance, long service life Self-lubricating Acetal polymer sheave ensures low friction and extreme durability Slotted pin shackle eliminates fouled lines Lockable swiveling head post Snap fit removable becket pin All purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads.
For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing. Head can be locked at 0° or 90° by engaging the grub screw in either the 0 or 90 degree position.
Applications: Mainsheet and halyard applications, vang and spinnaker control lines on boats to 10m (33ft) S60 - on boats up to 12m (40ft) Materials: Grade 316 stainless steel load strap Impact and UV resistant, fiber reinforced Nylon cheeks
Specifications
| Brand | Ronstan |
|---|---|
| Part Number | RF51300 |
| EverTide SKU | 70685 |
| UPC | 9316800241279 |
| Material | Stainless Steel |
| Cable Length | 33 ft |
| Beam Angle | 90° |
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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