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Ronstan Series 25 Ball Bearing Orbit Block™ - Lashing

SKU: ronrf28109  |  Manuf. Code: RF28109
$16.35 USD
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DESCRIPTION

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 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.

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.

Our Part # RONRF28109 | Mfr. Part # 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.

TECHNICAL INFORMATION

SpecificationValue
ManufacturerRonstan
Manufacturer part numberRF28109
Max. Rope diameter (in)5/16
Sheave diameter (in)1
B.L. (lb)1650
Weight (oz)0.5
BB Sheave and ballsHigh compression strength acetal.
Frame/cheeksToughened, glass-fiber-reinforced nylon.
Supplier technical detailDesigned 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 detailEach 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 detailThe hub accommodates up to 4mm (5/32") lashing and ensures maximum efficiency without compromising reliability.
Supplier technical detailSuits up to 8mm (5/16”) lines.
Supplier technical detailLashing blocks suit up to 4mm (5/32”) lashing.
Supplier technical detailMainsheet and spinnaker sheet turning blocks on dinghies to 4m (13ft).
ApplicationsMainsheet and spinnaker sheet turning blocks on dinghies to 4m (13ft). Control lines. Cascading vangs. Leech lines & cunninghams.
MaterialsBB Sheave and balls: High compression strength acetal. Frame/cheeks: Toughened, glass-fiber-reinforced nylon.
Product-name configurationLashing