Series 40 All-Purpose Single Block
General application plain-bearing blocks provide performance and value.
A smooth and efficient block is critical to the conversation between sailor and boat—especially for handheld control lines. Ronstan designed the Series 40 All-Purpose blocks to give dinghy and small keelboat sailors the feedback to detect subtle wind changes and sail as efficiently as possible.
These lightweight blocks feature a durable, self-lubricating, UV stable acetal sheave that runs smoothly on a Grade 316 stainless steel shaft. Fiber reinforced nylon cheeks provide rigidity and strength and are beefed up with 316 stainless steel load straps. The included shackle features a screw 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 40 All-Purpose blocks.
This 40mm 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.
- Lightweight blocks designed for moderate to high static and dynamic loads
- Ideal for handheld control lines
- Captive lock secures swivel at 0° or 90° or left to swivel freely
- Sliding acetal plain bearing on 316 stainless steel shaft 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 lightweight
- Grade 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)
Series 40 All-Purpose Single Block
|Ball Bearings||Plain Bearings|
|Diameter||7/16 Inch or 11 mm|
|Integral Cleat||No Integral Cleat|
|Mount Type||Swivel Shackle|
|Safe Working Load||882 Pounds|
|Sheave Diameter||40 mm|
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