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Ronstan Series 75 Core Block - Single [RF74100]

Regular price
$153.85
Regular price
$181.00
Sale price
$153.85
Shipping calculated at checkout.

SKU: CWR-55264   UPC: 9316800413225

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Series 75 Core Block™ - Single

Core Blocks™ are a true all round solution. A tuned 2-stage bearing system provides excellent performance across the full working load range with an integrated thrust bearing feature and the resilience to handle high dynamic or static loads. Acetal sheave, alloy cheeks and stainless fixings complete the durable package. For reliability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.

Universal Bearing
Dynamic and high static load performance

The Ronstan Universal Bearing incorporates our proven 2-stage bearing system

Stage 1 - Under moderate loads, Acetal ball bearings ensure minimum friction.

Stage 2 - Under heavy loads, where deformation of ball bearings alone would result in increased friction, a sliding Acetal bearing on a polished stainless steel race takes over, maintaining low friction performance.

Additionally the ball bearings are configured to act as a thrust bearing between the sheave and cheeks, preventing the sheave from rubbing on the cheeks and causing friction when the line lead in and out of the block isn't perfect. Particularly important for cheek blocks.

Alloy Cheek Plates
Block cheeks are manufactured from the highest quality alloy for maximum strength. Material optimisation and the cut-away design minimises weight and allows easy fresh water rinsing of salt and debris from the bearings. Cheek design has been further styled with flaring at the block throat and reduced gap between the cheek and sheave, minimising rope wear.

Universal head
The head assembly incorporates a brass bearing washer to provide smooth 360™ rotation of the post and shackle. A set screw arrangement allows the head to be locked at 0™ or 90™.

Shackles are high quality forged grade 316 stainless steel.

Features:

  • Class leading performance and sleek, contemporary styling
  • Excellent dynamic and high static load performance
  • Less than half the friction of the nearest competitor
  • Universal head with full 3-axis articulation
  • Head posts can be locked at 0 or 90 degrees, by using a 2.5mm Hex/Allen Key
  • Central hub hole can be used as a becket take-off or tie-up point


Applications:
  • Ideal for mainsheet, halyard and spinnaker sheet applications on boats to 14M (46')
  • Various control line applications on larger yachts


Materials:
  • Sheave: U.V. stabilized Acetal
  • Cheek body: Aluminium Alloy
  • Ball Bearings: High compression strength carbon black Acetal
  • Shackle, head post & hub: Grade 316 stainless steel


Specifications:
Sheave Ø:t75mm(3")
Max. Rope Ø:t14mm(9/16")
Pin Ø:t8mm(5/16")
M.W.L.:t1,500kg(3,300lbs)
B. L.:t3,000kg(6,600lbs)
Weight:t354g(12.5oz)

🚚 Shipping & Fulfillment

Many items at Lotz Outdoors ship the same day when ordered
by 2pm EST, so you can get your gear quickly for your next adventure.

Some products are fulfilled directly from our trusted
third-party partners. As a result, these items may:

• Ship separately from other items in your order

• Have different shipping rates

• Not be eligible for free shipping promotions

We work hard to keep shipping fast, reliable,
and transparent across our entire catalog, and any differences will be clearly
shown at checkout.

⚠️ Shipping restrictions

Shipping restrictions apply to certain products. By purchasing, you confirm compliance with all local, state, and federal laws.

We reserve the right to cancel any order based on our compliance policies.

⚠️ California Proposition 65 Warning

⚠️ WARNING: This product may contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.

This may include but is not limited to:
- Lead and lead compounds
- Nickel and nickel compounds
- Phthalates (DEHP, DBP, BBP, etc.)
- Bisphenol A (BPA)
- Cadmium and cadmium compounds

For more information go to www.P65Warnings.ca.gov

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Ronstan Series 75 Core Block - Single [RF74100]