The entire sheet is a very strong magnet! The magnetic sheet is made from thick (approximately 2mm), flexible magnetic material that weathers well even in wet or extreme weather conditions. Stick on some letters or a logo and it is ready to attach to something metal for a creative 'plain sight' cache!
Approximate dimensions are 19cm x 19cm, and 2mm thick.
Red bar on image is for scale, and measures 5cm.