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    • Ronstan Series 55 Ball Bearing Orbit Block  Single  Becket  Swivel Head RF55110
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    Ronstan Series 55 Ball Bearing Orbit Block - Single - Becket - Swivel Head [RF55110]

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    Sale Price $50.58 Regular Price $59.51
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    Series 55 Ball Bearing Orbit Block™ - Single - Becket - Swivel Head

    Lightweight
    Kilogram for kilogram of working load, BB and RT Orbit Blocks™ are the world's lightest. The unique orbital design allows the bearing to only be in the active areas of the floating sheave. This minimises the mass of the inactive return race and hub.

    Weight and bulk are further reduced in the different block configurations. The ball bearing single and becket block has a through-sheave becket arrangement. The result? The lowest weight possible.

    Multi-sheave blocks have only single intermediate cheeks and an ultra-light and efficient head arrangement. This gives a 30% weight saving advantage over the nearest competitor. Other brands just link together their single blocks. This results in unnecessary double cheeks between each sheave, held together by a heavy steel channel across the top of the block.

    Highest Working Load In Its Class
    The orbital ball-bearing arrangement gives the largest possible bearing race diameter. This maximises load performance. The proven Ronstan 2-stage bearing system features high compression grade acetal ball bearings and a secondary full-contact bearing. This gives minimum friction across the full working load range.

    The floating sheave and bearing system is supported by a fiber-reinforced load frame. The design was computer modelled to be stress optimised. The Dyneema® Link is produced from FSE Robline SK75 fiber, which is 10 times stronger and lighter than steel, and provides the final connection from the block to the load point.

    Features:

    • Ultra Lightweight
    • Low friction 2-stage Orbital ball bearing system
    • Highest working load in its class
    • Low profile and compact
    • High performance cleating
    • Swivel shackle head for unlimited block rotation
    • Stainless steel shackle head for ultimate durability and compatibility with harsh fixing points
    • Ultra low profile integrated becket


    Applications:
    • Mainsheet systems on dinghies, sportsboats and small keelboats to 9M(30')
    • Spinnaker sheets on dinghies, sportsboats and small keel boats to 9M(30')
    • Halyard, Vang and Backstay application on boats to 8M(26')
    • Control line applications on larger yachts
    • Ideal use for mainsheet systems and spinnaker sheets on dinghies, sportsboats and small keel boats to 9M(30')
    • Also ideal with halyard, vang and backstay applications on boats to 8M(26')
    • Spinnaker sheets on sportsboats and small keel boats (lateral lead blocks)
    • Control line applications on larger yachts


    Materials:
    • Ball bearings - High compression strength carbon black Acetal
    • Stage 2 bearing - Carbon fiber reinforced, PTFE impregnated Nylon
    • Frame/Cheeks - Toughened, glass fiber reinforced Nylon
    • Rope Link: UV stabilized, multi-strand impregmented SK75 Dyneema®
    • Sheave: Carbon fiber reinforced, PTFE impregnated Nylon
    • Head fitting: Grade 316 stainless steel.


    Specifications:
    Sheave Ø: 55mm(2-5/32")
    Max. Rope Ø: 10mm(3/8")
    M.W.L.: 500kg(1,100lbs)
    B. L.: 1,000kg(2,200lbs)
    Weight: 88g(3.1oz)
    Product Specifications
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    Documents
    User Manual Download
    Specification Sheet Download
    Safety Guide Download
    Service & Support

    Warranty

    This product is backed by a 12-month limited warranty, covering defects in materials and workmanship under normal use.

    Technical Assistance

    Our dedicated support team is available to assist with product setup, operation guidance, and troubleshooting. Contact us via email or phone for prompt service.

    Documentation & Downloads

    Access essential resources including the user manual, technical specifications, and safety instructions in our online support center.

    Replacement Parts & Accessories

    We offer a full range of genuine replacement parts, including batteries, chargers, and compatible accessories to ensure long-term performance.

    Training & Tutorials

    Browse our library of how-to videos and maintenance tips to get the most out of your cordless drill.

    FAQs

    Find quick answers to common questions

    Product & Usage

    1. Is your gear authentic and warranty-backed?

    Yes — we are an authorized US dealer for 300+ marine electronics brands. Every order ships with the manufacturer’s full warranty.

    2. Are these products beginner-friendly?

    Yes. Our products are designed for both seasoned boaters and first-time owners. Each unit ships with a manufacturer manual, and we’re happy to answer setup questions over email.

    3. Are these products built for marine conditions?

    Yes. Marine electronics are engineered for saltwater spray, vibration, and weather. Check the product specs for IPX waterproof rating and saltwater certifications.

    Maintenance & Accessories

    1. What maintenance does marine electronics require?

    Rinse with fresh water after saltwater exposure, store in a dry place, and follow your manufacturer’s cleaning and storage instructions.

    2. Can I buy replacement parts and accessories separately?

    Yes — we carry replacement parts, mounts, transducers, cables, and accessories for the brands we stock.

    3. Do you provide product manuals or installation guides?

    Every product ships with the original manufacturer’s manual. Digital copies and detailed installation guides are typically available on the brand’s website.

    Warranty & Guarantee

    1. Does my purchase include a warranty?

    Yes — every order includes the full manufacturer warranty. Coverage length varies by brand (typically 1–3 years for Garmin, Lowrance, Raymarine, Simrad, Humminbird, Furuno, and others).

    2. How do I register for warranty coverage?

    Register directly with the manufacturer using your unit’s serial number. Manufacturer registration is the fastest path to warranty support if you ever need it.

    3. What does the manufacturer warranty cover?

    Defects in materials and workmanship under normal use. Damage from impact, improper installation, or saltwater corrosion (without protection) may be excluded. Check brand-specific terms in your unit’s documentation.

    4. Can I extend the warranty?

    Some manufacturers offer extended-coverage programs through their registration portals. We don’t sell third-party warranty programs.

    Purchasing & Support

    1. How fast does my order ship?

    Orders placed before 4pm EST Monday–Friday ship the same business day via UPS from our NJ or FL warehouses. Continental US delivery typically takes 3–7 business days for Economy.

    2. Do you offer bulk or fleet pricing?

    Yes — we offer volume pricing for fleet operators, marinas, dealers, and commercial customers. Email support@marineelectronicsdepot.com with your needs.

    3. How can I contact support?

    Email support@marineelectronicsdepot.com or call during business hours (Mon–Fri 9am–5pm ET). We’re happy to help with pre-purchase questions, order status, or post-sale support.

    Can’t find your answer?

    Feel free to reach out to us!

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