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- USA
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Ships within 48 hours · Estimated delivery Jul 6 - Jul 11
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Description
Ronstan 60mm Mast Base, 8mm (5/16") Clevis Pin Head Core BlockProduct Description Ronstan 60mm Mast Base, 8mm (5 16") Clevis Pin Head Core Block Features Class leading performance and sleek, contemporary styling Excellent dynamic and high static load performance Less than half the friction of the nearest competitor Durable aluminum alloy cheek plates Central hub hole can be used as a becket take off or tie up point Suits attachment to 14mm (9 16) wide mast collar post Removable 8mm (5 16) clevis pin at head
Product Description
Ronstan 60mm Mast Base, 8mm (5/16") Clevis Pin Head Core Block
Features
Class leading performance and sleek, contemporary styling
Excellent dynamic and high static load performance
Less than half the friction of the nearest competitor
Durable aluminum alloy cheek plates
Central hub hole can be used as a becket take-off or tie-up point
Suits attachment to 14mm (9/16”) wide mast collar post
Removable 8mm (5/16”) clevis pin at head
Measurements
Sheave Ø - 2 3/8 in. (60 mm)
Max. Rope Ø - 1/2 in. (12 mm)
Max. Cable Ø - in (mm)
Pin Ø - 5/16 in. (8 mm)
M.W.L. - 2200* lb. (1000* kg)
B. L. - 4410* lb. (2000* kg)
Weight - 6.4 oz. (182 g)
Product Information
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 optimization and the cut-away design minimizes 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, minimizing rope wear.
Applications
Ideal for mainsheet, halyard and spinnaker sheet applications on boats to 12m (40ft).
Various control line applications on larger yachts.
Alloy sheave models are available for use with wire.
Materials
Sheave: U.V. stabilized Acetal or anodized aluminum (AW models)
Cheek plates: Aluminum alloy
Ball Bearings: High compression strength carbon black Acetal
Pin: 2205 stainless steel
Features
Measurements
Sheave Ø - 2 3/8 in. (60 mm)
Max. Rope Ø - 1/2 in. (12 mm)
Max. Cable Ø - in (mm)
Pin Ø - 5/16 in. (8 mm)
M.W.L. - 2200* lb. (1000* kg)
B. L. - 4410* lb. (2000* kg)
Weight - 6.4 oz. (182 g)
Product Information
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 optimization and the cut-away design minimizes 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, minimizing rope wear.
Applications
Materials
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- 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
4.2 ★★★★★
Based on 995 reviews
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Product Reviews
★★★★★ 5
Durable
Color: Dogwood (Brown), Size: Large (Pack of 1)
Durable, good chew toy.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 8, 2026
★★★★★ 5
GREAT TOY
Color: Dogwood (Brown), Size: Large (Pack of 1)
My 6m old Shepard Terrier LOVES this toy. He loves chewing on wood and we’ve gotten him all types of chew toys but I’ve never seen any toy keep him this busy and interested. Buy if ur dog chews furniture!!!!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on June 13, 2026
★★★★★ 4
Large is a little big for Bostons
Color: Dogwood (Brown), Size: Large (Pack of 1)
Seems to be durable for 2 VERY agressive chewer Boston Terriers. Cricket and Alice are shockingly good at chewing - grateful they pick to do so with thier toys.
Trial vs other name brand competitor.
PetStages' is a little larger so harder to bite on fir small dogs, but seems to be equally durable. While PetStages proudly states it has real wood fiber and scent (whoch I thought would win)... they prefered the other. Both dogs love to chew on real sticks.
But, when the bossy one indicated she was taking over the stick the other dog had, they exchanged, and kept chewing, over and over, back and forth. I mean to say, whatever the prefered stick was at first didnt seem to matter later.
These super hard chew toys do make me nervous. One dog broke a tooth last summer on a different brand toy, a very expensive extraction bill, and poor pup's terrible discomfort... but the other did not and has amazing white teeth, all around.... so.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on September 26, 2025
★★★★★ 5
Great for teething puppies
Color: Dogwood (Brown), Size: Small (Pack of 1)
My pup absolutely loves this. Can keep him occupied for up to 45 min at a time. Pretty durable, too.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 8, 2026
★★★★★ 5
The best chew ever for a strong chewer
Color: Dogwood (Brown), Size: Large (Pack of 1)
We have a 77lb goldendoodle who loves these. We’re lucky because he doesn’t chew on anything other than his toys, but when he starts on this…he really goes at it. It’s healthy, (not synthetic), doesn’t break apart, (no pieces to worry about him swallowing), it just perfect for him. The noise may get on your nerves but it’s a small price to pay to keep him from chewing on your furniture, shoes, or anything else a mischievous dog can find.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 30, 2026
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