as the strength depends on how much of the magnet's surface directly contacts the metal

you should latch onto part of the frame where the magnet has a strong hold

The metal balls are also called metal spheres

Lyseblå gummimagnet

Magnetiske tal extra 2 - Magnetfolie 10x15 cm. (4-pak) Auto-translated (EN) as the strength depends onWhite magnetic foil with black number "2" printed on the front. Each number is A6 size (approx. 10x15 cm.) and this is a pack of 4 additional number 2s. Great for time, date and calculations on magnetic boards. Colour of magnetic foil: White. Colour of numbers: Black. Thickness: 1 mm. Strength: approx. 80 g. cm2. Content: the number 2 (4 pcs.) Magnetic sheets are made of magnetic foil and can adhere magnetically on metal cabinets, whiteboards and