The string is inside a case on a reel, with chalk powder inside it. As you run it out, chalk coats the string. You then pull it tight between two points, pull it back, and release it.
It leaves a dead straight line of chalk behind, you then roll it back up ready to be reused. You can also buy replacement chalk.
The string is inside a case on a reel, with chalk powder inside it. As you run it out, chalk coats the string. You then pull it tight between two points, pull it back, and release it.
It leaves a dead straight line of chalk behind, you then roll it back up ready to be reused. You can also buy replacement chalk.
https://www.bunnings.co.nz/irwin-30m-strait-line-chalk-reel-and-line-level-set_p5660558?store=9526
Oh that’s way more practical than anything I was coming up with! Nice.