The diameter refers to the distance between the two widest points of the button horseshoe magnet’s circular surface. The diameter ranges from 12.5mm (0.5″) to 32mm (1.3″).
A large diameter button horseshoe magnet is useful for clamping two large pieces of steel together, whereas a smaller diameter would be more suited to holding thin pieces of steel. This is because the larger the diameter, the greater surface area of magnet is available to hold the large pieces of steel together.
The height refers to how tall the magnet is and ranges from 9.5mm (0.4″) to 25.4mm (1″).
A tall button magnet will be beneficial whilst being used as a magnetic base. This is because it will provide added height and allow the implement, e.g. an inspection mirror, to be within an easier reaching distance of the user (it will be higher off the surface).
The diameter of the clearance hole ranges from 4.5mm (0.2″) to 10mm (0.4″).
The diameter of clearance hole matters when purchasing a button horseshoe magnet to act as a magnetic base. This is because the diameter of the stand on the inspection mirror, for example, will dictate the diameter of the clearance hole so that they can fit together, e.g. a 9mm diameter inspection mirror stand will fit into a 10mm clearance hole.
The magnetic pull ranges from 0.7kg (1.5lb) to 4.8kg (10.6lb).