Unique design prevents scratching of the glass and maximizes the force on the cleaning blades. The magnet itself is 3mm from the glass, only the cutting edges of the blades make direct contact. Additionally the use of a short blade and a long blade creates a varying pressure so aggressive detail cleaning may be done with the short blade and the wide blade handles general clean up. Additionally a stainless steel blade can be fitted to the wide blade for heavy jobs. Note: only the short blades are acrylic safe, scope of Delivery includes 2 short blades, 2 long blades and 1 stainless blade, 2 blades must be used to avoid damage. Care magnet long is suitable for 3/8-1/2" glass or acrylic.