SKU: 5750437443

Ronstan Series 45 Core Block™ - Single - Swivel Shackle Head

Sale price$64.48 Regular price$71.64
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Ships within 48 hours · Estimated delivery Jul 23 - Jul 28

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Description

Ronstan Series 45 Core Block™ - Single - Swivel Shackle HeadSeries 45 Core Block Single Swivel Shackle Head 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,

Series 45 Core Block™ - Single - Swivel Shackle Head

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.

Features:
  • High dynamic and static load capacity
  • Efficient 2-stage bearing system
  • Ball bearings to counteract side thrust loads
  • Class leading performance and sleek, contemporary styling
  • Durable aluminium alloy cheek plates
  • 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 10M (33')
  • Various control line applications on larger yachts
  • Alloy sheave models are available for use with wire


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: 45mm(1-3/4")
Max. Rope Ø: 12mm(1/2")
Pin Ø: 5mm(3/16")
M.W.L.: 700kg(1,540lbs)
B. L.: 1,400kg(3,090lbs)
Weight: 104g(3.6oz)
Manufacturer : Ronstan
Manufacturer Part No : RF44100
UPC : 9316800466153
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: 5750437443

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Nicole
Los Angeles, US
★★★★★ 4
Great
Size: 3 Fl Oz (Pack of 1), Style: SPF 50
The sunscreen itself is really good. It applies smoothly just as advertised “lotion”. I was pleased to see it didn’t leave a white cast. I apply makeup over my sunscreen often. This sunscreen worked perfectly with makeup. Like it said, it’s unscented and that was true as I didn’t detect a scent. My skin feels nice with this on. My only issue is that it didn’t come with a safety seal under the cap. Usually all products come with a seal to ensure it isn’t tampered with and that buyer gets the full amount of product. That was a bit upsetting but hopefully I didn’t actually get a used one.
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Reviewed in the United States on April 3, 2026
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Effee
New York, US
★★★★★ 5
Sheer Sensitive SPF 50 ☀️
Size: 6 Fl Oz (Pack of 1), Style: SPF 50, Size: 6 Fl Oz (Pack of 1), Style: SPF 50
Application: Specifically purchased for use on the face. ​ Finish: Leaves the skin feeling moisturized, not greasy. ​ Appearance: Blends in perfectly with no white cast. ​ Value: Highly concentrated formula—a little goes a long way. ​ Verdict: A rare mineral-based sunscreen that actually feels lightweight and looks invisible on the skin. Ideal for daily protection without the heavy, oily feel of traditional sunscreens.
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Reviewed in the United States on April 27, 2026
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sunnyberry
Draper, US
★★★★★ 5
I LOVE this sunscreen!! Super affordable and lightweight for your skin!
Size: 6 Fl Oz (Pack of 1), Style: SPF 50
I love this sunscreen!! Love it so much I bought 3 bottles of it! Super lightweight and blends right into the skin, and I don’t feel not sticky! I got super excited and got this primarily because it’s lightweight, super affordable, SPF 50 for high protection, and it said there’s no alcohol or fragrance…heres the catch tho, there IS a slight sunscreen smell, but you only notice it when applying it and if you keeping smelling it on yourself up close during the day. Other than that, it’s truly fragrance free in the sense that you aren’t just standing there doing your thing, and keep getting HIT with the scent of sunscreen for hours, like other sunscreens! The scent is extremely light and pleasant when you go to smell it on yourself. Don’t EVER discontinue this please please please!!!!
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Reviewed in the United States on May 26, 2026
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Lemonie
Natrona Heights, US
★★★★★ 5
It’s great! So light weight!
Size: 3 Fl Oz (Pack of 1), Style: SPF 50
I have been testing this out for a month now. I love it. This does have avobenzone in it, and because of that, I do NOT put it around my eyes as avobenzone is a chemical sunscreen ingredient that typically tends to cause the of sensation of burning eyes! At least for me it does. I use an Australian sunscreen around my eyes that doesn’t have anything that irritates my eyes. So for the rest of my face, this stuff is great. It literally is so serum like sinks into your skin within five minutes or sooner. Now it’s not the most hydrating thing in the world so if you have a dry skin, you still wanna go in with a moisturizer before however, if you have oily skin, this is your girl right here. Skin like finish, not super matte and not dewy at all. I do not wear primer so I don’t know how it plays with that. Works great under my makeup and has never caused pilling. Quick, easy, simple ingredients, definitely sensitive skin friendly, and no fragrance at an affordable cost-effective price! Now if only banana boat decided to go cruelty free😭 9/10 bc not CF 💔
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Reviewed in the United States on April 27, 2026
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Linsey R.
Battle Creek, US
★★★★★ 5
Great sensitive skin sunscreen
Size: 3 Fl Oz (Pack of 1), Style: SPF 50
Love this! I have sensitive skin. this did not sting my eyes, or burn my cheeks. Left no white cast. I'm not noticing any scent. It just feels like bare skin, it's not heavy, drying, oily or sticky. No pilling. Went on smooth, not streaky, looks like skin once dried down, not patchy. I hope they keep this in stock forever!
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Reviewed in the United States on March 27, 2026

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