Click to enlargeRonstan Series 40 All Purpose Block - Single - Stand Up
Manufacturer: RonstanPart #: RF41140SKU: 55205
- 880 lb
- Stainless Steel
Add $62.88 more to qualify for free shipping.
Item #: 55205
Category: Blocks
● In stock — ships fast from US warehouses
- Ships from US warehouses
- Free shipping on orders over $99
- Secure checkout — your info is protected
- Genuine marine-brand parts, not knockoffs
- 30-day returns
- Marine parts support — we know boats
Description
Series 40 All Purpose Block - Single - Stand Up 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. Captive Lock™ universal head can be fixed in either of two planes, or free to swivel as required.
Features: Exceptionally high working loads Low maintenance, long service life Self-lubricating sheave Captive Lock™ universal head Mount with 2 x 5mm (3/16") fasteners (not supplied) Applications: Mainsheet Halyard Vang Spinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8M(26') Materials: U. V.
stabilized Acetal sheaves Impact and U. V.
resistant, fiber reinforced Nylon cheeks Grade 316 stainless steel bearing race Grade 316 stainless steel load strap and head fitting Specifications: Sheave Ø: 40mm(1-9/16") Max. Rope Ø: 10mm(7/16") M.
W. L.
: 400kg(880lbs) B. L.
: 800kg(1,760lbs) Weight: 72g(2. 5oz)
Specifications
| Brand | Ronstan |
|---|---|
| Part Number | RF41140 |
| EverTide SKU | 55205 |
| UPC | 9316800244362 |
| Material | Stainless Steel |
Specifications are provided by the manufacturer. Confirm fitment for your application before ordering, or contact us and we'll help.
Compare similar products
![]() | ![]() | ![]() | ![]() | |
|---|---|---|---|---|
| Material | Stainless Steel | Stainless Steel | Stainless Steel | Stainless Steel |
Complete your setup
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.
Customer reviews
No reviews yet — this product.
Fast shipping
Ships from US warehouses — free over $99
The right part
Marine-grade parts matched to your boat
Real support
Questions? We know boats — call or email




