Marshalltown 16504 Cast Aluminum Line Stretchers

Product Description

The MARSHALLTOWN 16504 is a pair of cast aluminum line stretchers designed to hold and tension mason lines between key course blocks during masonry layout work. The stretchers are fully adjustable from 4 inches to 12 inches, allowing a single tool to accommodate varying block widths and wall thicknesses without swapping out hardware. The cast aluminum construction keeps weight low while maintaining the rigidity needed to hold a taut line under field conditions. Masons and masonry contractors use these to establish straight, level course lines across block or brick work, making them a standard layout tool on residential and commercial masonry jobs.

These line stretchers are suited for use on concrete masonry unit (CMU) block walls, brick courses, and similar masonry applications where consistent line tension is critical to maintaining level courses. The adjustable range of 4 to 12 inches makes them practical for standard block widths commonly encountered in residential foundations, retaining walls, and commercial block construction. They are sold as a pair, which is the standard configuration for spanning a wall section between two corner or key blocks.

Key Features

• Fully adjustable from 4 inches to 12 inches to fit varying block widths
• Cast aluminum construction for lightweight durability
• Sold as a pair for immediate use on a wall section
• Holds mason lines taut between key course blocks for accurate layout
• Packaged in a poly bag with header card for jobsite storage and retail display

Compatibility

Designed as a standard replacement or additional pair of line stretchers for use with mason line on CMU block and brick masonry courses requiring adjustable line tensioning between key blocks.

Installation Notes

Line stretchers are installed by masonry tradespeople as part of wall layout and course alignment. No power tools or fasteners are required. Position each stretcher securely on the key course block before tensioning the mason line to prevent slippage. Inspect the stretchers for wear or deformation before each use to ensure consistent line tension throughout the course.

Technical Specifications

• Adjustment Range: 4 to 12 inches
• Material: Cast Aluminum
• Quantity: Pair (2 pieces)
• Weight: 4.38 pounds
• Unit of Measure: Each
• Package Quantity: 6

Standard Information

• Brand: MARSHALLTOWN
• Manufacturer Part Number: 16504