Rather than add more current limit circuits, many manufacturers chose to ignore the requirement and increase the current limits above 20 A per rail, or provided "single-rail" power supplies that omit the current limit circuitry. (In some cases, in violation of their own advertising claims to include it.) Because of the above standards, almost all high-power supplies claimed to implement separate rails, however this claim was often false; many omitted the necessary current-limit circuitry, both for cost reasons and because it is an irritation to customers. (The lack was, and is, sometimes advertised as a feature under names like "rail fusion" or "current sharing".)