Series 25 Ball Bearing Orbit Block - Lashing

Single sheave ball bearing block with becket and lashing head.

The Series 25 Ball Bearing Orbit Blocks deliver 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 metres.

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


• Sheave diameter (in): 1


• B.L. (lb): 1650


• Weight (oz): 0.5

Applications:

• Mainsheet and spinnaker sheet turning blocks on dinghies to 4m (13ft).


• Control lines.


• Cascading vangs.


• Leech lines cunninghams.

Materials:

• BB Sheave and balls: High compression strength acetal.


• Frame/cheeks: Toughened, glass-fiber-reinforced nylon.