"Theoretically, any issuer could carve out an Aa2' class," said a rating agency source who preferred to remain anonymous, citing the Rule 144A transaction's private status. "But for most issuers, it's uneconomical; there would need to be a lot of enhancement."The triple-A class of Providian Gateway 2004-A was supported by 47% enhancement, which gave Providian plenty to carve out for the sector's first natural double-A rated bonds. Of this, the double-As represented only 8% of the deal. PGMT 2004-A also has a funded 3.5% segregated reserve account, which could trap excess spread should the deal hit performance triggers.