General application blocks provide performance and value.
A smooth and efficient block is critical to the conversation between sailor and boat—especially for hand-held control lines. Ronstan designed the Series 50 All-Purpose blocks to give dinghy and small keelboat sailors the feedback to detect subtle wind changes and sail as efficiently as possible. These light-weight blocks feature a durable, self-lubricating, UV stable acetal sheave that runs smoothly on a 316 stainless steel bearing. Fiber reinforced nylon cheeks provide rigidity and strength and are beefed up 316 stainless steel load straps. The included shackle features a pin with a low-profile head to prevent snagging on smaller lines. Get the messages your boat sends you though the lines by using efficient and smooth Ronstan Series 50 All-Purpose blocks.
This 50mm single with shackle head is versatile and can be used for a wide range of applications. Great for halyard tuners, Cunninghams, dinghy sheets and more.
Key Features
- Light weight blocks designed for moderate to high static and dynamic loads
- Ideal for hand-held control lines
- Captive lock secures swivel at 0° or 90° or left to swivel freely
- Sliding acetal bearing on 316 stainless steel race handles high loads and maintains low friction
- Fiber reinforced nylon cheeks to add strength while reducing weight
- Self-lubricating, UV stable acetal sheave is strong and light-weight
- 316 stainless steel load straps add strength
- Ideal for:
- Dinghy and small keelboat sheets
- Halyard tuning systems
- Backstay systems on dinghies and smaller keelboats
- Boom vangs (cascade systems)
Ronstan Selection Guide
| Sheave Diameter | Line Compatibility | Shackle Pin Diameter |
|---|
| 20mm | 1/4" (6mm) | 1/8" |
| 30mm | 5/16" (8mm) | 5/32" |
| 40mm | 3/8" (10mm) | 3/16" |
| 50mm | 1/2" (12mm) | 3/16" (1/4" for Double and Triple blocks) |
