SKU: 88815645907

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

Sale price$45.52 Regular price$50.58
Save 10%

Pay in installments of $12.64 with ShopPay, AfterPay and Klarna

Shipping Estimate
USA
  • USA
  • CAN

Ships within 48 hours · Estimated delivery Aug 15 - Aug 20

Promo Codes Available:

For Your Every Summer RSVP, with Code: SUMMER15

Description

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

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)
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: 88815645907

Discover Niche Categories That Outsell

Top-Converting Item to Boost Your Average Order

4.0 ★★★★★
Based on 13 reviews
Sort
Highest Rating
Newest First
Oldest First
Product Reviews
A
Verified Purchase
anthony f. san felippo
West Palm Beach, US
★★★★★ 5
Great Product
Size: Combo Pack (26" & 20"), Style: Top Lock Narrow
Fits my 2022 Tesla Model S Plaid perfectly! Easy to install and cheaper than going through Tesla
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 5, 2026
S
Verified Purchase
shamimur rahman
West Palm Beach, US
★★★★★ 5
Great item
Size: Combo Pack (26" & 20"), Style: Top Lock Narrow
Great item. Works & fits well on Tesla Model Y 2023
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 7, 2026
A
Verified Purchase
Amos
Lowell, US
★★★★★ 5
Smooth and quiet wipe
Size: Combo Pack (26" & 20"), Style: Top Lock Narrow, Size: Combo Pack (26" & 20"), Style: Top Lock Narrow
Swapped these onto my car and they work great. Installation was quick and easy, took just a couple minutes. The wipe is smooth and quiet with no streaks, even in heavier rain. Feels like a solid upgrade compared to cheaper blades I’ve used before. So far very satisfied.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 2, 2026
P
Verified Purchase
Perez
Alexandria, US
★★★★★ 4
Great fit...but 1" shorter
Size: Combo Pack (26" & 20"), Style: Top Lock Narrow
Fit and quality is great. However the shortblade needs to be 21". OEM is26" and 21". Bosch sets 26 and 20". I may have missed, but I didnt t see anyone mentioning this issue. Other than that is perfect fit.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 18, 2026
F
Verified Purchase
Fat Kat
Bozeman, US
★★★★★ 5
Terrific Bosch blades
Size: Combo Pack (26" & 20"), Style: Top Lock Narrow, Size: Combo Pack (26" & 20"), Style: Top Lock Narrow
These German made wiper blades do their job so well that my wife was impressed. Once you get the hang of it they are one minute to replace. Recommend placing a cloth under the blade to avoid any windshield scratches if the metal wiper assembly accidentally falls down on the glass. Nice to see the Bosch name on the wiper blades.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 22, 2026

recommand products