Selden BBB40 Fiddle Ball Bearing Block with Swivel – 40 mm / 20 mm

The Selden BBB40 fiddle ball bearing block with swivel is designed for cascading and multi-purchase systems where compact layout and efficient load distribution are essential. The fiddle configuration combines two sheaves of different sizes, enabling optimized control and mechanical advantage in tight rigging spaces.

The 40 mm primary sheave and smaller secondary sheave run on stainless steel ball bearings, ensuring smooth rotation and minimal friction even under dynamic loads. This results in precise trimming and reduced effort during operation.

The swivel shackle ensures optimal alignment under load and can be fixed or allowed to rotate freely depending on the setup. This flexibility makes the block suitable for a wide range of control line configurations.

Constructed from glass fibre reinforced composite with an acetal bearing cage, the block offers a strong, lightweight and durable solution for demanding marine environments.

Key features:

• Fiddle block (dual sheave sizes) for cascading systems
• Swivel head for optimal alignment
• Stainless steel ball bearings for smooth operation
• Low friction under dynamic loads
• Compact design for efficient rigging layouts

Technical specifications:

• Sheave diameter: 40 mm (main)
• Max line diameter: 10 mm
• Safe working load: 250 kg
• Breaking load: 500 kg
• Pin diameter: 4 mm
• Shackle diameter: 4 mm
• Weight: approx. 158 g

Applications:

• Cascading and fine-tuning systems
• Outhaul and Cunningham setups
• 4:1 purchase systems
• Dinghies and performance keelboats