Ronstan RF25109 Series 20 Orbit Block Single Becket Ball Bearing

The Ronstan RF25109 is a lightweight, high-strength single block with lashing becket designed for modern rigging systems using high-tech lines. Part of the innovative Orbit Series 20 line, this block delivers an exceptional strength-to-weight ratio, weighing just 9 grams (0.3 oz) while safely handling loads up to 550 lbs.

Key Features:

• Ultra-lightweight design at under 9 grams with 550 lb working load capacity
• Two-stage ball bearing system: 316 stainless steel ball bearings handle light to moderate dynamic loads, while slide bearings manage heavier static loads
• Lashing-only installation accepts up to 4mm dyneema or other high-tech lines
• Glass fiber reinforced nylon frame and cheeks for maximum strength with minimal weight
• UV-resistant high-compression acetal sheave for smooth operation with conventional and high-tech lines
• 20mm sheave diameter compatible with 1/4" (6mm) line
• Single becket configuration for multi-purchase systems
• Ideal for dinghy control lines, small sailboat applications, and weight-critical rigging

By eliminating traditional shackle pin posts and unnecessary metal components, the Orbit Series 20 achieves remarkable weight savings without compromising the proven performance Ronstan blocks are known for. The efficient bearing system ensures smooth operation under varying loads, making this block perfect for performance sailing applications where every gram matters.