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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:
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200 14th Avenue Southeast, St. Petersburg, FL 33701
7C San Bartola Drive, Saint Augustine, FL 32086




We bought these boots in 2022, and are buying new ones 3 years later. We love the design and the fact that they are easy to remove for inspection of the rig.
Review for electrical system components:
• Victron Lithium Battery 24VDC 300Ah NG Smart LifePO4 (x4)
• Victron Lynx Smart BMS 500 NG (M10)
• Victron Lynx Distributor w/M10 Terminals (x2)
• Victron MultiPlus-II 24/5000 120-95 120V (x2)
• Victron Phoenix Smart IP43 Charger 24/25 (1+1) 120-240VAC (x5)
• Victron Cerbo GX MK2 w/ Victron GX Touch 70 Flush Mount Display
• Z Bar - Class T battery link Bundle w/ Blue Sea 5119 300AMP Class T Fuse (x4)
• Victron Orion XS 1400 DC-DC Battery Charger (x2)
• Victron SmartSolar MPPT Charge Controller - 100V - 30AMP - UL Approved (x4)
Complete upgrade of my Irwin 54 Sloop electrical system –
Phase 1 – Remove 9KW generator, install 30KW LifePO4 battery system, inverter chargers, battery chargers, etc. wired for worldwide shore power capability to ABYC standards. Installation made possible with guidance and support from Andre Cormier and The Yacht Rigger.
I was amazed with the product especially, the attention to detail. I was also very pleased with the help and recommendations I received from Chris Wilcher. He made the purchase very easy.
I was very pleased with the product especially, the attention to detail. I was also pleased with the support I received from Chris Wilcher. He made the purchase very easy.
The Z Bar Class T Fuse Holder solves a real problem, and does so in a simple and affordable way.

