Ronstan Series 30 Ball Bearing Orbit Block™, Lashing RF35101

Ronstan Series 30 Ball Bearing Orbit Block™ Lashing – RF35101

The Ronstan Series 30 Ball Bearing Orbit Block™ Lashing RF35101 is an ultra-lightweight, high-strength single-sheave block designed for modern performance sailing systems. Featuring a Dyneema® lashing head, low-friction 2-stage bearing system, and exceptional strength-to-weight ratio, it is ideal for dinghies, skiffs, sportboats, and high-performance rigging applications.

The Ronstan Series 30 Ball Bearing Orbit Block™ Lashing RF35101 is engineered to deliver maximum performance with minimal weight. Designed using advanced composite materials and innovative load management technology, it offers one of the highest strength-to-weight ratios available in a sailing block.

Unlike traditional blocks that rely on heavy stainless steel load straps and shackles, the Orbit Block™ range utilises fibre-reinforced composite construction and a lightweight Dyneema® lashing attachment system. This significantly reduces weight while maintaining exceptional strength and durability in demanding marine environments.

The RF35101 features Ronstan's proven 2-stage bearing system, combining high-compression acetal ball bearings with a secondary full-contact bearing. This design delivers consistently low friction across the entire working load range, ensuring smooth operation whether lightly loaded or under significant tension.

The integrated lashing head provides versatile attachment options and allows the block to be aligned in either 0° or 90° orientations for optimal rigging efficiency. The ultra-low-profile through-sheave becket further reduces bulk while enabling clean and efficient purchase systems.

Constructed with a carbon black acetal sheave, high-strength acetal ball bearings, toughened glass fibre reinforced nylon cheeks, and a UV-stabilised SK75 Dyneema® link, the RF35101 is built for long-term reliability and performance.

Ideal for traveller systems, vang purchases, cascades, control lines, mainsheet systems, and lightweight running rigging, the Series 30 Orbit Block™ is a favourite among performance sailors seeking maximum efficiency with minimum weight.

Key Features

• Exceptional strength-to-weight ratio
• Lightweight Orbit Block™ design
• Single sheave block with becket
• Dyneema® lashing head attachment
• 2-stage low-friction ball bearing system
• Consistent performance across full load range
• Fibre-reinforced composite construction
• Ultra-low-profile through-sheave becket
• 0° or 90° attachment orientation options
• High-strength carbon black acetal sheave
• UV-stabilised SK75 Dyneema® attachment link
• Compatible with RF1850S shackle if required

Ideal For

• Dinghy sailing
• Skiff racing
• Sportboats
• Foiling classes
• Traveller systems
• Vang purchases
• Cascade systems
• Mainsheet systems
• Control line applications
• Lightweight performance rigging

Technical Specifications

• Model: RF35101
• Series: Ronstan Series 30 Orbit Block™
• Block Type: Single Sheave Block with Becket and Lashing Head
• Sheave Diameter: 30mm
• Maximum Rope Diameter: 8mm
• Maximum Working Load (MWL): 300kg
• Breaking Load (BL): 600kg
• Weight: 22g
• Sheave Material: Carbon Black Acetal
• Ball Bearings: High Compression Acetal
• Frame/Cheeks: Glass Fibre Reinforced Nylon
• Attachment Link: UV-Stabilised SK75 Dyneema®

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