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Ronstan Series 25 Ball Bearing Orbit Block - Lashing [RF28109]

Authorized Ronstan Dealer
Genuine Product
Save $2.88 Save $2.88
Original price $19.23
Original price $19.23 - Original price $19.23
Original price $19.23
Current price $16.35
$16.35 - $16.35
Current price $16.35
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Availability:
5+ in stock, ready to be shipped
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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.

No manual is available for this product.

Estimated Delivery Time: 1-7 business days.

  • Orders placed before 1PM CST will ship the same day. All other orders will ship the next day.
  • Transit Time: 1-6 business days

Click here to view our full Shipping Policy.

Returns accepted within 30 days.

  • Items must be new, unused, and in original packaging.
  • Returned merchandise may be subject to a restocking fee of up to 15%

Click here to view our full Return & Refund Policy.

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