K2 Systems Rail Connector Splice CR 44-X Mill 4000051

The K2 Systems Rail Connector CR 44-X 4000051 is a structural external rail splice designed to securely connect sections of K2 CrossRail 44-X in photovoltaic mounting systems. Its external mounting design allows the connector to join adjacent rail sections without occupying the internal rail channel, leaving valuable space available for wire management and other system components.

Manufactured from aluminum with a mill finish, the connector attaches to the CrossRail using two stainless steel T-bolts and serrated flange nuts. K2 identifies the 4000051 as a true structural connector specifically engineered for the CrossRail 44-X platform.

The connector measures approximately 177.8 mm (7.00 in) long and provides a simple slide-in installation method. Its combination of structural strength, corrosion-resistant materials, and streamlined installation makes it a dependable rail-splicing solution for K2 rooftop solar mounting systems. 

Key Technology

• Structural Rail Connection
  Designed as a true structural connector for joining two sections of K2 CrossRail 44-X.

• CrossRail 44-X Compatibility
  Purpose-built for use with K2 CrossRail 44-X mounting rails.

• External Connector Design
  Mounts externally to the rail rather than occupying the internal channel, helping preserve internal rail space for wire management.

• Simple Slide-In Assembly
  Designed for straightforward positioning and installation between adjoining rail sections.

• Two T-Bolt Attachment Points
  Secures to the rail using two M10 × 20 stainless steel T-bolts and matching serrated flange nuts.

• Aluminum Construction
  Manufactured from durable aluminum for a strong yet lightweight solar mounting connection.

• Mill Finish
  Natural mill aluminum finish matches compatible mill-finish CrossRail components.

• 25-Year Warranty
  Backed by a 25-year K2 Systems manufacturer warranty.

• Florida Product Approval
  Listed under Florida Product Approval FL#46869 as part of the K2 mounting system documentation.

Best Uses

• CrossRail 44-X Rail Extensions
  Ideal for structurally joining two CrossRail 44-X sections when a longer continuous rail run is required.

• Residential Rooftop Solar
  Suitable for K2 CrossRail rooftop PV mounting systems using mill-finish 44-X rails.

• Long Rail Runs
  Provides a secure structural splice where individual rail lengths must be connected to span larger arrays.

• Wire-Management-Friendly Installations
  The external connector leaves the internal CrossRail channel available for routing and organizing PV wiring.

Product Specifications

Structural Rail Splicing for K2 CrossRail 44-X

The K2 Systems Rail Connector CR 44-X 4000051 provides a durable structural connection between adjoining CrossRail 44-X sections. With its aluminum construction, external mounting design, stainless steel hardware, simple slide-in assembly, and 25-year warranty, it provides a reliable solution for extending rail runs while keeping the internal rail channel available for cable management.

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Our inventory is updated daily with the latest solar technologies, and our experienced team is ready to assist with product selection, system design, and installation guidance.

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