Ronstan Series 25 Ball Bearing Orbit Block with Becket & Swivel Shackle – RF28100

Series 25 Ball Bearing Orbit Block - Becket Swivel Shackle

Single sheave ball bearing block with becket hub and swivel shackle head.

Series 25 Ball Bearing Orbit Blocks, delivering superior strength, reduced weight, and exceptional performance for high-demand dinghy and small boat applications.

Designed with competitive sailors and performance boats in mind, these compact 25mm blocks are engineered to achieve the highest possible strength-to-weight ratio. Featuring Ronstans renowned high compression strength acetal bearing system, the Series 25 BB Orbit Blocks are a lightweight yet durable solution, ideal for control line systems such as mainsheet and spinnaker sheet turning blocks, cunninghams, and cascading vangs on dinghies up to 4 meters.

Each block has a stainless steel hub for versatile lashing attachments and through-sheave becket functionality, making them adaptable to a wide range of rigging setups. The hub accommodates up to 4mm (5/32) lashing and ensures maximum efficiency without compromising reliability.

Features:

• 2-stage ball bearing system.
• Suits up to 8mm (5/16) lines.
• Hollow hub for becket take-off.
• Lashing blocks suit up to 4mm (5/32) lashing.

Specifications:

• Max. Rope diameter (in): 5/16
• M.W.L. (lb): 500
• Sheave diameter (in): 1
• B.L. (lb): 990
• Weight (oz): 0.6

Applications:

• Mainsheet and spinnaker sheet turning blocks on dinghies to 4m (13ft).
• Control lines.
• Cascading vangs.
• Leech lines cunninghams.

Materials:

• Frame/cheeks: Toughened, glass fibre reinforced nylon.
• BB Sheave and balls: high compression strength acetal.

The Ronstan Series 25 Ball Bearing Orbit Block with Becket & Swivel Shackle (RF28100) is a high-performance, lightweight solution designed for demanding sailing applications. Crafted with precision, this compact 25mm block features a robust ball bearing system that ensures smooth operation and minimal friction, making it ideal for control lines such as mainsheets, spinnaker sheets, and cascading vangs on small dinghies up to 13 feet. Its high compression strength acetal bearings provide durability while maintaining a low weight profile, essential for competitive sailing where performance and reliability are paramount. The stainless steel hub allows versatile lashing attachments and accommodates up to 4mm lashing, ensuring secure mounting and flexible rigging options. Its through-sheave becket design simplifies line routing, reducing wear and tear over time, and enhancing overall efficiency. The frame and cheeks are constructed from toughened glass fiber reinforced nylon for durability, while the sheave and ball bearings are made from high-strength acetal, ensuring long-lasting performance even under high loads. Whether used as mainsheet or spinnaker sheet turning blocks, control lines, or cascading vangs, this orbit block offers superior strength-to-weight ratio and dependable operation. Its compact size, combined with high-quality materials, makes it an excellent choice for sailors seeking precision and durability in small boat rigging setups. The Series 25 orbit block is engineered for ease of use and maximum performance, providing a reliable component for high-demand sailing environments.

Features:

• Two-stage ball bearing system for smooth operation

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

• Hollow hub design for becket take-off

• Lashing compatibility up to 4mm (5/32 inches)