Ronstan Series 75 Core Block - Single [RF74100]
SKU: 24372248717

Ronstan Series 75 Core Block - Single [RF74100]

Sale price$138.47 Regular price$153.85
Save 10%

Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Jul 8 - Jul 13

Promo Codes Available:

For Your Every Summer RSVP, with Code: SUMMER15

Description

Ronstan Series 75 Core Block - Single [RF74100]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

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: 75mm(3")
Max. Rope Ø: 14mm(9/16")
Pin Ø: 8mm(5/16")
M.W.L.: 1,500kg(3,300lbs)
B. L.: 3,000kg(6,600lbs)
Weight: 354g(12.5oz)

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 24372248717

Discover Niche Categories That Outsell

Top-Converting Item to Boost Your Average Order

4.9 ★★★★★
Based on 955 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
M
Verified Purchase
Miah
Phoenix, US
★★★★★ 5
Solid Floating Shelves 🛠️🏠
Color: Black, Number Of Shelves: 4, Size: 15.7in
I have installed four sets of the black floating shelves in my office. They are made of high quality materials, featuring a sophisticated black woodgrain finish with a natural texture. Supposedly, each unit can handle up to 22 pounds, though I would not recommend testing that limit with your vintage bowling ball collection if you value your flooring. They are awesome. The value is good for a set of two. Each shelf measures 22x7x1 (56x17x3 cm) inches, providing a decent amount of storage for books or decor. The installation was straightforward since the hardware for multiple wall types was included. They work well in the kitchen for spices or in the bedroom for personal belongings. One tip for a secure fit: use a level during installation and make sure the bracket is flush against the wall before sliding the shelf on, or your photos might look like they are sliding off a mountain 📐 These shelves offer a clean, modern look and stay stable once mounted correctly. They are a practical choice for adding functional display space to any room 🖼️
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 4, 2026
T
Verified Purchase
Tyler Kline
Los Angeles, US
★★★★★ 5
Good looking shelves and easy install - skip the included drywall anchors
Color: Black, Number Of Shelves: 2, Size: 22in
I installed these shelves in a bedroom to get things off my dresser and some decor. Once mounted they look really nice. The black finish looks clean and modern and they blend in well with the room. Installation was pretty straightforward. The metal bracket mounts to the wall first and then the shelf slides over the bracket. As long as you take your time lining things up it’s a simple project. One thing I strongly recommend is not using the white plastic self-drilling drywall anchors that come with the kit. I’ve used that style before on other projects and they tend to strip out easily and leave larger holes in drywall. I used better anchors instead and the shelves mounted much more securely. The rest of the hardware worked fine and once installed the shelves feel solid and hold items well. Pros - Clean modern look - Easy installation - Feels solid once mounted - Good size for books or decor Cons - The small level included isn’t very accurate — use your own level - One of the metal brackets was slightly bent out of the box but straightened out easily Helpful tip: Use your own level and better drywall anchors if you have them. It makes installation easier and the shelves will mount much more securely. Final thoughts: For the price these are nice looking floating shelves that install easily and work well for light storage and decor.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on March 13, 2026
C
Verified Purchase
Coffman, H
Los Angeles, US
★★★★★ 5
Cheap, and effective!
Color: Black, Number Of Shelves: 4, Size: 15.7in
Looks good, works great, low cost. I'll be purchasing more in the future.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 12, 2026
A
Verified Purchase
Amazon Customer
Lake Worth, US
★★★★★ 4
Cute for coffee bar!
Color: Black, Number Of Shelves: 4, Size: 15.7in
Great for above my coffee bar. Easy to mount and align. Seems stable!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 14, 2026
S
Verified Purchase
Samuel Roberts
Whiting, US
★★★★★ 5
Great shelves, strong, secure, sturdy, decent size, unbeatable price.
Color: White, Number Of Shelves: 4, Size: 15.7in
Easy installation fits where we wanted them. Stable strong secure snug fit. Cleans easily with dust wipe. I would recommend buying these.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 19, 2026

recommand products