The Ronstan Series 50 All Purpose Fiddle Block is designed for consistent performance in both cruising and racing applications. Featuring a self-lubricating Acetal polymer sheave on polished stainless steel races, this block provides low friction and high load capacity for sheets, halyards, and control lines. The assembly includes a multi-position cleat arm and a Captive Lock universal head that can be set to a fixed plane or allowed to swivel.
Key Features:
- Exceptionally high working loads for reliable performance
- Durable, impact and UV-resistant fiber-reinforced nylon cheeks
- Grade 316 stainless steel load strap
- Captive Lock universal head for flexible orientation
- Slotted pin shackle prevents line fouling
- Removable snap-fit becket pin for easier splicing
- Quick-adjusting cleat arm requires no tools
- Compatible with boats up to 10m (33ft)
- Recommended for mainsheet tackles, cunninghams, backstays, and control line systems
Replacement Parts:
- RF51010 Replacement Becket Pin
- RF150 Shackle
Product facts
- CT SKU
- CT-114662
- Model / MPN
- RF51530
- UPC / GTIN
- 9316800241392
- Package dimensions
- 3" X 5" X 7"
- Package weight
- 0.72 lb
Fit-sensitive item: confirm measurements, model numbers, and manufacturer details before ordering. Tug & Tow does not guarantee universal compatibility from a product page alone.
Shipping & returns
Shipping & returns
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Fit & compatibility
Fit & compatibility
Review the product title, description, images, dimensions, part numbers, and manufacturer details before purchase. For fit-sensitive items, confirm compatibility with your boat, RV, trailer, vehicle, or equipment.
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Need help choosing?
Send us the product link or SKU, plus details about your boat, RV, trailer, vehicle, or project. We will help you narrow down the right option when product fit is not obvious.
