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Ronstan Series 75 Core Block - Single
Vendor: Ronstan
SKU: CW55264UPC: 9316800413225
$130.90
Available in stock (15)
Free Shipping on orders over $99.99ETA delivery: Fri, Jul 10 – Thu, Jul 16
30-Day ReturnsEligible unused items may be returned within 30 days with an RMA number. See Return Policy for return shipping details.Order with confidenceFree standard shipping over $99.99 to the 48 contiguous U.S. states. Eligible unused items may be returned within 30 days with an RMA number.View Shipping & Returns
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.
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.
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Free shipping over $99.99 to the 48 contiguous U.S. states
US Shipping
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Shipping Details30-Day Returns
Return eligible unused items within 30 days of delivery with an RMA number.
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