What technical specs to ask from a CE-certified magnetic window cleaner supplier?

“Ask for glass thickness range (5 to 35 mm ideal), magnet grade (neodymium preferred), holding force at each thickness increment, battery capacity (≥2200 mAh), motor duty cycle, safety sensor type (IR or Hall effect), IP rating for water resistance, and the exact CE test standard applied. A complete technical datasheet should accompany every quotation.”