Schaefer Spring-Loaded Block provides full rotation and articulation.

Schaefer Stand up spring block for 1" T-Track with Delrin™ sheave ensures smooth operation and high safe working load. Anodized aluminum cheeks and stainless steel slider allows for effortless running. Polyethylene liner and pin stop allow for easy adjustment. 

Used extensively for sheet blocks on small- to mid-sized keelboats, and as control line blocks for larger offshore boats. Suitable as mast-base or lead blocks on small- to mid-sized boats.  Black anodized aluminum or stainless steel cheeks. Stainless steel straps and posts. 

Key Features 

• Swivels 45° to each side of the track
• Stainless steel slider
• Patented design prevents block from hitting the deck
• Captive liner allows block to glide along the track without friction   
• Universal design suits diverse applications and mounting options
• Tough, hardcoat-anodized aluminum cheeks 
• Smooth UV resistant, Delrin™ sheave
• Accepts Schaefer "universal" adapters for custom mounting
• High strength to weight ratio