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Ronstan

Ronstan Series 25 Ball Bearing Orbit Block™ - Lashing

Ronstan Series 25 Ball Bearing Orbit Block™ - Lashing

SKU:110654

Regular price $33.99
Regular price Sale price $33.99
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  • Genuine brand-name parts
  • Ships from US warehouse
  • 30-day returns

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.

Brand Ronstan
Manufacturer part number RF28109
UPC / GTIN 9316800661923
Weight 0.05 lb
Category Marine & Boating
Condition New — genuine brand-name product
Genuine brand-name product, full manufacturer warranty. Ships from the closest US warehouse — normally within 1–3 business days. Questions before you order? Send us the manufacturer part number above and we’ll confirm. 30-day returns on unused items.

Shipping & delivery

Orders ship from the distributor warehouse closest to you, normally within 1–3 business days of purchase. Standard ground delivery takes 3–7 business days in the continental US; expedited options are shown at checkout. Oversized items (bumpers, running boards, large tonneau covers, some marine equipment) ship LTL freight — we contact you to schedule delivery and a signature is required.

Returns & warranty

Unused, uninstalled parts in original packaging can be returned within 30 days of delivery. A restocking fee of up to 20% may apply depending on the product and supplier, and return shipping is the buyer’s responsibility unless the item arrived defective, damaged or incorrect. Every product carries the full manufacturer warranty. Contact us with your order number to start a return.

Fitment & part numbers

Verify fitment with the manufacturer part number shown above and your vehicle’s year, make, model and trim. If the listing says “Fits select…”, confirm your exact application before ordering. Not sure? Send us your VIN and the part number and we’ll check it for you.

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