(Bankrate) — NPSL credit cards aren’t your typical credit cards. “No preset spending limit” doesn’t mean unlimited spending potential, as the fine print for these cards will tell you. In some cases, issuers of NPSL cards may simply not disclose the spending limit to the cardholder and approve transactions at their discretion. In other cases, they’ll disclose a revolving credit line and approve transactions that exceed it at their discretion, without imposing an overlimit penalty. NPSL cards also differ in their repayment terms. For example, the charge cards from American Express require monthly charges to be paid in full, while others operate as charge card/credit card hybrids, only requiring payment in full for the amount charged over the revolving credit line.