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Ronstan
S25 BB Orbit Block, Single, Becket, Lashing
Single sheave ball bearing block with becket and lashing head.
Special Price
16.36€
was
16.87€
On Request
SKU
RF28109
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.
Materials
BB Sheave and balls : High compression strength acetal.
Frame/cheeks: Toughened glass fibre reinforced nylon.
| Type of Block | Single |
|---|---|
| Sheave diameter (mm) | 25mm |
| B.L. (kg) | 550 |
| M.W.L. (kg) | 250 |
| Max. Rope diameter (mm) | 8 |
| Weight (g) | 14 |
| Sheave Material | Acetal |
| Notes: | Both the MWL & BL are dependent on the strength of line used to lash the block through the central hub. Knots, splices, stitching will generally have a lower BL than the line itself. |
The 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 Ronstan’s 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.
- Mainsheet and spinnaker sheet turning blocks on dinghies to 4m (13ft).
- Control lines.
- Cascading vangs.
- Leech lines & cunninghams.