Series 25 Single Utility Block
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RONSTANSeries 25 Single Utility Block


In stock online.
Model # 538678 | Mfg # RF573UPC # 9316800003877
Series 25 Single Utility Block




Series 25 Single Utility Block

Name Value
Ball Bearings Plain Bearings
Becket No Becket
Diameter 1/4 Inch or 6 mm
Direction Any
Integral Cleat No Integral Cleat
Mount Type Swivel Shackle
Ratchet Non Ratcheting
Safe Working Load 330 Pounds
Sheave Diameter 25 mm
Type Single
Weight 0.7 Ounce

Product Overview

A simple, economical plain bearing utility block with a swivel shackle.

Not all control line blocks on a boat require two-stage bearings that evolve from years of R&D—and the expense that goes with them. Sometimes the system just needs a simple, but solid block. Utility blocks are just the answer for these situations, but Ronstan takes simple a step further by using top quality materials.

Commonly used for dinghy applications, these blocks feature 316 stainless steel cheeks for strength and superior corrosion resistance. UV stable acetal sheaves provide durability for a long service life.

Each block is riveted together and requires virtually no maintenance—just a little rinse now and again. The rivets are hollow and can be used to fasten the blocks with screws, shackles or lashed. For extra purchase the rivet can be used as a becket. There is a utility block for almost any light to moderate load application. 

Key Features

  • Solid simple plain bearing block
  • 316 stainless steel cheeks for strength and superior corrosion resistance
  • Acetal sheaves offer UV resistance
  • The 5/32" shackle pin feature a low-profile head that fastens with a flat head screwdriver
  • Riveted together
  • Can be mounted using fasteners, shackles or lashed
  • Ideal for general control lines, sheets, spinnaker controls, turning blocks, Cunninghams and outhauls


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