Magnets mounted on steel backplate, typically used to attach signs attach signs to the roofs of vehicles, e.g. taxi signs, breakdown trucks, delivery vans.

Magpad
Supplied with 16mm M6 bolt and nut
79 x 53 x 12mm
Max pull force of 9kg

Mini Magpad
2 x 5mm holes to allow fixing
90 x 30 x 7.5mm
Max pull force of 12kg