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Ronstan RF15101 Series 15 Ball Bearing Block Single Loop Top

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

RF15101
09/12/2036 8:02 AM
Sale Price

$10.74

In Stock (5)

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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 Series 15 Ball Bearing Single Block is an ultra-compact, lightweight block featuring a 5/8" diameter sheave with exceptional strength-to-weight ratio. This micro block delivers ball bearing performance in the smallest package available, making it ideal for dinghies, small sailboats, and creative rigging applications.

Key Features:

  • Precision-molded UV-stabilized acetal sheave running on stainless steel ball bearings for smooth, low-friction operation
  • 316 grade stainless steel cheeks, headpost, shackle, and ball bearings for maximum corrosion resistance in marine environments
  • Single loop head design with O-ring separator to prevent interference between running line and attachment hardware
  • Smallest and lightest ball bearing block on the market at just 0.3 oz (7 g)
  • Versatile applications including cunninghams, vangs, tweakers, shock cord retractors, and purchase systems
  • Ideal for youth sailing classes (Optimist, El Toro, Sabot) and high-performance dinghies

Specifications:

  • Sheave Diameter: 5/8" (15 mm)
  • Maximum Line Diameter: 3/16" (5 mm)
  • Maximum Working Load: 260 lbs (120 kg)
  • Breaking Load: 1,210 lbs (550 kg)
  • Weight: 0.3 oz (7 g)

Perfect for sailors looking to reduce weight and add efficient mechanical advantage in space-constrained applications. The combination of ball bearing technology and micro dimensions makes this block suitable for both marine and land-based rigging projects.

Products specifications

Type

Single

Diameter

3/16 Inch or 5 mm

Ball Bearings

Stainless Steel

Becket

No Becket

Direction

Any

Integral Cleat

No Integral Cleat

Great so far

Great price and shipping is more than reasonable.

found part after lots looking glad to find it.

thanks for having such great prices

Fast shipping, very helpful staff, product was in stock at Autoplicity and I couldn't even find it at any other supplier. Thanks Autoplicity!

Thanks

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