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Ronstan RF35151 Series 30 Ball Bearing Orbit Block Cheek 30mm

Manufacturer

Ronstan

<h3>Ronstan: Precision Sailing Hardware Built for Every Sailor</h3><p><strong>Ronstan</strong> is one of the most respected names in sailboat hardware — and with good reason. <a href="/11561-ronstan">Ronstan</a> traces its roots back to 1953, when two Australian sailors, Ron Allatt and Stan Lenepveu, founded Ronstan Marine Equipment Pty Ltd in Melbourne, Australia. What started as a passion project supplying handcrafted yacht fittings to their local sailing club gradually grew into a global enterprise recognized for engineering excellence and real-world performance.</p><p>Today, Ronstan is headquartered in Braeside, Victoria, Australia, with international offices in the United States and Denmark, and production facilities across three continents. The brand distributes to more than 40 countries and handles upwards of 4.9 million units out of its Melbourne facility every year. In November 2023, Ronstan joined Groupe Wichard, further cementing its place among the world&apos;s most influential marine hardware groups.</p><h3>Engineering That Performs On the Water</h3><p>What sets Ronstan apart from generic marine suppliers is its deep commitment to innovation and in-house manufacturing capability. Ronstan&apos;s engineering teams — spread across Australia, the United Kingdom, and Denmark — draw on diverse sailing traditions to develop products that meet the demands of wildly different markets: from club dinghy racers to offshore bluewater cruisers. The brand&apos;s catalog spans blocks, winches, travelers, furling systems, batten systems, stainless steel rigging hardware, and a full suite of deck gear. Ronstan is also the official hardware supplier to the Australian Sailing Team.</p><p>The brand&apos;s in-house manufacturing includes precision CNC machining of aluminum, brass, and stainless steel, as well as advanced plastic injection molding using high-performance engineering polymers — including composites reinforced with up to 60% long-strand glass and carbon fiber. This vertical integration means Ronstan controls quality from design to delivery.</p><h3>Core Product Categories</h3><p>Three categories stand out as workhorses of the Ronstan lineup. <a href="/11561-ronstan-fairleads-200387">Ronstan Fairleads</a> are purpose-designed to guide, contain, and correct the lead angle of control lines across a range of deck configurations — a deceptively simple piece of hardware that plays a critical role in clean, friction-free sail handling. For securing lines under load, <a href="/11561-ronstan-cleats-200268">Ronstan Cleats</a> offer a comprehensive range spanning jam cleats, vee cleats, and the brand&apos;s well-known C-Cleat&trade; and T-Cleat&trade; cam cleat families, each engineered for reliable cleating and easy release in all conditions. Completing the rigging equation, <a href="/11561-ronstan-shackles-200937">Ronstan Shackles</a> — including the innovative Triggersnaps&trade; snap shackle range — are individually proof-load tested and designed for intuitive one-handed operation, making them a trusted choice for racers and cruisers alike.</p><h3>From Dinghies to Maxis</h3><p>One of Ronstan&apos;s most distinctive qualities is its breadth. The same brand that equips Olympic-class dinghies also supplies hardware to some of the largest and fastest offshore racing yachts in the world. Whether you&apos;re outfitting a small club boat or a serious offshore campaigner, Ronstan&apos;s catalog has a solution engineered to the right weight, load rating, and finish for the task at hand.</p>

Part Number

RF35151
09/13/2036 6:00 AM
Sale Price

$14.58

In Stock (10+)

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Usually delivered within 2 days

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No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Ronstan RF35151 Series 30 Orbit Block is a lightweight, high-performance 30mm cheek block designed for modern sailing rigging systems. This versatile block excels at turning lines along deck surfaces and flat mounting applications, making it ideal for barber-haulers, downhauls, travelers, outhauls, and control line systems on dinghies through larger yachts.

Advanced Two-Stage Bearing System:

Ronstan engineered the Orbit Block series to deliver the highest strength-to-weight ratio in its class. The innovative two-stage bearing system provides exceptional efficiency across the entire load range. High compression grade acetal orbital ball bearings automatically migrate to loaded areas of the sheave for light to moderate loads, while a full-contact PTFE-impregnated nylon bearing with carbon fiber reinforcement handles higher static loads with ease.

Lightweight Composite Construction:

Through extensive computer modeling, Ronstan replaced unnecessary metal components with engineered composites without compromising strength. The glass fiber-reinforced nylon cheeks and head design can be secured using the supplied loop or converted to soft attachment with a Dyneema link for further weight reduction. The hollow bearing at the sheave center serves double-duty as a becket, adding versatility while minimizing weight.

Key Features:

  • 30mm UV-resistant acetal sheave compatible with 5/16" (8mm) conventional doublebraid and high-tech 12-strand lines
  • Shackle pin diameter: 5/32"
  • Highest working loads in class with exceptional strength-to-weight ratio
  • Dual bearing system optimizes performance under both static and dynamic forces
  • Hollow sheave bearing doubles as becket attachment point
  • Glass fiber-reinforced nylon cheeks for durability
  • Optional angled pad compatibility for improved line scope
  • Convertible attachment: supplied loop or soft Dyneema link

The RF35151 delivers smooth, efficient line handling even under larger loads, making it an ideal solution for modern control line applications where weight savings and performance are equally critical.

Products specifications

Diameter

5/16 Inch or 8 mm

Mount Type

Mechanical Fasteners

Type

Single Cheek/Foot

Becket

No Becket

Direction

Any

Integral Cleat

No Integral Cleat

Ratchet

Non Ratcheting

Safe Working Load

661 Pounds

Sheave Diameter

1 3/16 Inches or 30 mm

Easy internet access. fast shipping. justlike the advertise.

Quick and easy

Fast,prompt service and delivery. Very pleased.

Good

Very high level of responsive customer service, wow! And the items arrived immediately, so fast I thought there might be a mistake. :D<br>thx Sean!

good price on intake.shipping to high on other items

Great prices, quick shipping, customer service a bit difficult to reach. But, after reaching customer service, issue was resolved without a problem.

great place to order honda parts from ! i will definitely use this siye in the future

price was great

I assume that the parts are for the driver side and passenger side lower control arm, even though it is not specifically stated . It would be much clearer if it stated this in ad. Thanks DPL

Easy, fast and very helpful via phone

Great Prices

Best price I could find! Shipped through UPS, great service.

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