With its uniform radial expansion throughout the entire fastener grip, Radial-Lok® is uniquely suited to offer both enhanced fatigue strength and lightning strike damage protection.

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Key Features

  • Uniform radial expansion throughout the entire length of the clearance fit hole
  • Interference fits to .006″
  • Enhanced fatigue life
  • Better lightning strike protection
  • Eliminates costly hole preparation
  • Clearance fit before installation
  • Easy one sided installation
  • High clamp up
  • Large blind side upset
  • Tighter joints
  • Ideal for aluminum and composite applications
  • Available in 3/16″ through 3/4″ diameters including oversizes
  • .100″ grip accommodation
  • 7 degree blind slope capability

The most versatile blind fastener for a variety of applications

Radial-Lok® diagram with descriptionsThe ability of the Radial-Lok® to expand (.002″ to .006″) uniformly throughout the entire length of the hole greatly increases the fatigue life of the fastener and assures structural integrity under severe cyclic loading conditions in both aluminum and composite structures. With Radial-Lok®’s .003″ hole tolerance these benefits are achieved without the costly preparation of close tolerance or tapered holes required by some fasteners.

Radial-Lok®’s unique characteristics make it the most versatile blind fastener for a variety of applications in both composite and aluminum structures. It is completely compatible with graphite and is not subject to galvanic corrosion. In addition, Monogram’s Drive Nut system greatly simplifies the installation of Radial-Lok® fasteners.

Comparative photos show the benefits of the Radial-Lok® fasteners unique hole filling properties as compared to a conventional fastener. Bands shown are made visible by viewing a bi-refringent plastic through polarizing filters.

Part Numbers & Technical Drawings

Part FamilyPrefixMaterialHead StyleShank TypeSpecial FeaturesRated Shear StrengthTechnical Drawing Downloads
Radial-LokMRL3210TitaniumProtruding, Low ProfileNominalRadial Hole Fill75 KSI MRL3210-REV-AP.pdf
Radial-LokMRL3212Titanium100 Degree TensionNominalRadial Hole Fill75 KSI MRL3212-REV-AF.pdf