Ronstan Series 25 Ball Bearing Orbit Block™, Lashing, RF28109

Ronstan Series 25 Ball Bearing Orbit Block™ – Single with Becket & Lashing Head

Lightweight 25mm ball bearing block with becket and lashing head, designed for high-performance dinghy control systems and rigging applications.

The Ronstan Series 25 Ball Bearing Orbit Block™ is engineered for high-performance dinghy sailing where strength, weight, and efficiency are critical. Designed with competitive sailors in mind, this compact 25mm single block delivers exceptional strength-to-weight performance for demanding control line systems.

Featuring a 2-stage ball bearing system with high compression strength acetal bearings, the block ensures smooth, low-friction operation under load. This allows for precise trimming and efficient load handling across a range of applications including mainsheet systems, spinnaker sheets, cunninghams, and cascading vangs.

The stainless steel hub is designed for versatile lashing attachments and incorporates a through-sheave becket for additional rigging flexibility. The hollow hub allows for efficient becket take-off, while supporting up to 4mm lashing line, making it adaptable to a wide range of custom setups.

Constructed with a toughened, glass fibre reinforced nylon frame, the Series 25 Orbit Block™ is built to withstand the rigours of high-load dinghy sailing while maintaining a lightweight profile. Suitable for lines up to 8mm, this block is an ideal choice for performance dinghies and small boats up to 4 metres.

Ideal For

• Dinghy sailing up to 4m (13ft)

• Mainsheet and spinnaker sheet systems

• Control line setups

• Cascading vang systems

• Cunninghams and leech lines

Key Features

• 2-stage ball bearing system for smooth, low-friction performance

• High compression strength acetal bearings for durability under load

• Stainless steel hub for versatile lashing configurations

• Through-sheave becket for additional rigging functionality

• Hollow hub design for efficient becket take-off

• Supports lashing lines up to 4mm (5/32")

• Suitable for control lines up to 8mm (5/16")

• Lightweight, compact design optimised for performance dinghies

• Toughened glass fibre reinforced nylon frame for strength and durability

Technical Specifications

Sheave Size: 25 mm
Line Capacity: Up to 8 mm (5/16")
Lashing Capacity: Up to 4 mm (5/32")
Bearing System: 2-stage ball bearing
Hub: Stainless steel, hollow for becket take-off

Materials:

• Sheave & Ball Bearings: High compression strength acetal

• Frame/Cheeks: Glass fibre reinforced nylon