400mm x 600mm
Types of Squares: https://www.doityourself.com/stry/infoaboutsquares
Article-How to use: https://www.johnsonlevel.com/News/FramingSquare
400mm x 600mm
Types of Squares: https://www.doityourself.com/stry/infoaboutsquares
Article-How to use: https://www.johnsonlevel.com/News/FramingSquare