DESCRIPTION
DESCRIPTION
Series 25 Ball Bearing HHL Lashing Orbit Block™
Single sheave ball bearing high load block with becket hub option 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 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.
The range also includes a High Load (HHL) variant – the RF28109HL – which is equipped with a Grade 2205 stainless steel sheave and bearing race, paired with Grade 304 stainless steel ball bearings. These HHL blocks are purpose-built for high-load applications and are increasingly in demand for modern performance and foiling boats using small-diameter lines to carry significant loads.
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): 880
- Sheave diameter (in): 1
- B.L. (lb): 2650
- Weight (oz): 1.2
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.
- HHL Sheave and bearing race: Grade 2205 stainless steel with Grade 304 stainless steel ball bearings.
Our Part # RONRF28109HL | Mfr. Part # RF28109HL
FEATURES
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.
TECHNICAL INFORMATION
TECHNICAL INFORMATION
| Specification | Value |
|---|---|
| Manufacturer | Ronstan |
| Manufacturer part number | RF28109HL |
| Max. Rope diameter (in) | 5/16 |
| M.W.L. (lb) | 880 |
| Sheave diameter (in) | 1 |
| B.L. (lb) | 2650 |
| Weight (oz) | 1.2 |
| Frame/cheeks | Toughened, glass fibre reinforced nylon. |
| HHL Sheave and bearing race | Grade 2205 stainless steel with Grade 304 stainless steel ball bearings. |
| Supplier technical detail | Designed with competitive sailors and performance boats in mind, these compact 25mm blocks are engineered to achieve the highest possible strength-to-weight ratio. |
| Supplier technical detail | 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. |
| Supplier technical detail | The hub accommodates up to 4mm (5/32") lashing and ensures maximum efficiency without compromising reliability. |
| Supplier technical detail | The range also includes a High Load (HHL) variant – the RF28109HL – which is equipped with a Grade 2205 stainless steel sheave and bearing race, paired with Grade 304 stainless steel ball bearings. |
| Supplier technical detail | Suits up to 8mm (5/16”) lines. |
| Supplier technical detail | Lashing blocks suit up to 4mm (5/32”) lashing. |
| Supplier technical detail | Mainsheet and spinnaker sheet turning blocks on dinghies to 4m (13ft). |
| Supplier material detail | HHL Sheave and bearing race: Grade 2205 stainless steel with Grade 304 stainless steel ball bearings. |
| 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. HHL Sheave and bearing race: Grade 2205 stainless steel with Grade 304 stainless steel ball bearings. |





