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S75 Core Block, Mast Base Block


Model # 13090824 | Mfg # RF74108A
Ships directly from the vendor

Core Block are a true all round solution. A tuned 2-stage bearing system provides excellent performance across the full working load range with an integrated thrust bearing feature and the resilience to handle high dynamic or static loads. Acetal sheave, alloy cheeks and stainless fixings complete the durable package. For reliability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing.

  • Sheave (in.): 3
  • Max. Rope (in.): 9/16
  • Max. Cable (in.): 5/16
  • MWL (lb.): 3000*
  • BL (lb.): 6600
  • Weight (oz.): 8.1


*Full block rated load can only be achieved with uniformly distributed load across full length of clevis pin. ie. 14mm (9/16”) diameter mast collar post or 14mm (9/16”) wide mast collar plate/tang.

S75 Core Block, Mast Base Block

Becket No Becket
Diameter 9/16 Inch or 14 mm
Direction Any
Integral Cleat No Integral Cleat
Mount Type Fixed Lashing Eye
Ratchet Non Ratcheting
Safe Working Load 3000 Pounds
Sheave Diameter 75 mm
Type Single
Weight 8.1 Ounces

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