These square discs are attachments for the Zebra range of line marking machines.
Designed for line marking on hard surfaces such as concrete and tarmac, they are installed either side of the spray nozzle (as pictured), in order to provide crisp and clean edges to the lines.
The distance between the two discs can be adjusted in order to set your required line width.
Made from metal, these discs are easy to clean after a line marking job.
If you have previously purchased a Zebra grass line marking machine with round discs, you can replace the round discs with these square discs to use your Zebra machine for hard surface line marking, such as marking car parks, industrial floors, hard sports courts and more.