These round discs are attachments for the Zebra range of line marking machines.
Designed for line marking on grass and artificial grass surfaces, 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 hard surface line marking machine with square discs, you can replace the square discs with these round discs. You can then use your machine to line mark all kinds of sports pitches and courts on grass and artificial grass line marking.