Restriction of Hazardous Substances Directive a disadvantage because it can lead to lower quality electrical connections – can be used to place components more tightly than they used to be placed due to the properties of lead-containing solders. For example, Motorola reports that their new RoHS wireless device assembly techniques are "...enabling a smaller, thinner, lighter unit." Their Motorola Q phone would not have been possible without the new solder. The lead-free solder allows for tighter pad spacing. Research into new alloys and technologies is allowing companies to release RoHS products that are currently exempt from compliance, "e.g." computer servers. IBM has announced a RoHS
Electrical element and they are assumed to have ideal properties, while actual electrical components have less than ideal properties, a degree of uncertainty in their values and some degree of nonlinearity. To model the nonideal behavior of a real circuit component may require a combination of multiple ideal electrical elements in order to approximate its function. For example, an inductor circuit element is assumed to have inductance but no resistance or capacitance, while a real inductor, a coil of wire, has some resistance in addition to its inductance. This may be modeled by an ideal inductance element in series with a resistance.