M-Series Single Block
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SCHAEFERM-Series Single Block


Limited availability.
Only 1 in stock!
Model # 8825135 | Mfg # M66-05UPC # 740507903656
M-Series Single Block




M-Series Single Block

Name Value
Ball Bearings Delrin
Becket No Becket
Diameter 1/2 Inch or 13 mm
Direction Any
Integral Cleat No Integral Cleat
Mount Type Swivel Shackle
Ratchet Non Ratcheting
Safe Working Load 2800 Pounds
Sheave Diameter 66 mm
Type Single
Weight 9 Ounces

Product Overview

Schaefer 66mm Single Block allows either a 2:1 or 3:1 purchase.  

Computer-machined aluminum construction maintains sideplate strength while minimizing weight, giving these blocks an incredible strength-to-weight ratio and a distinctive, clean look. Torlon™ rollers and Delrin® ball bearings in the sheave handle high loads with low friction. An excellent alternative for sailors interested in a lightweight choice.

Key Features 

  • CNC-machined aluminum with outstanding strength-to-weight ratio
  • Torlon™ rollers and Delrin™ ball bearings handle high loads with low friction
  • Finished in hardcoat anodized black for durability
  • Machined center of the block may be used as a "becket" 
  • Forged D Shackle on swivel head
  • Sheave Diameter: 2 5/8" (66 mm) 
  • Max. Line Diameter: 1/2" (13 mm)  
  • Safe Working Load (SWL): 2800 lb. (1270 kg)  
  • Weight: 9.0 oz (254 g) 
  • Length: 5 3/8" (137 mm)


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