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GRB104 Rooftop Support Block

Four-block base with 40” strut

Maximize the capabilities of your rooftop strut system with the quadruple-block base of the GRB104 model. The largest component of the G-STRUT© 100 series, the GRB104 features 40” of steel strut channel on tandem heavy-duty molded rubber base for UV-resistant, weather-resistant, strong and sturdy support. Wondering if the GRB104 is right for your project? The team at Gregory Strut can help you — reach out and give us a call.

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Product Details

A 100% recycled truck tire rubber base and 14-gauge pre-galvanized steel makes the GRB104 a versatile, all-weather option for any rooftop application. The steel strut channel works with standard strut channel fittings and clamps, while the rubber base is compatible with most commercial roofing materials. Combine with any of the G-STRUT© 100 Series base block components for a customized support system.

  • Four-block base with attached 40” strut channel
  • Pre-assembled at the factory
  • 14-gauge, 13/16” pre-galvanized steel channel
  • Uses standard strut channel fittings and clamps
  • 100% recycled rubber block
  • UV-resistant materials
  • Green high-visibility reflectors for safety
  • Innovative design inhibits floating and shifting
  • Freeze and thaw resistant
  • LEED certifiable product
  • Vibration dampening
  • Compatible with most rooftop materials


  • Basel length: 42 1/4"
  • Base width: 5 1/2”
  • Base height: 4”
  • Height: 4 13/16” (to top of the strut)
  • Channel width: 1 3/4”
  • Channel length: 40”
  • Materials: 100% recycled rubber base, pre-galvanized 14-gauge steel channel
  • Safety: Green reflector for high visibility
  • Weight: 21.2 lbs
  • Static load capacity: 1,000 lbs.
  • Ordering: 74 pieces per skid

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AD Electrical
NetPlus Alliance

Have a question?
Contact our Vice President of Gregory Strut, Bob Porter, to discuss your questions, goals and project requirements.

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