National Australia Bank returned to the asset-backed securities market late last week, after an absence of eight years. The A$400 million transaction involved the issue of securities backed by loan and lease receivables originated by NAB subsidiary Medfin.NAB will pay 65 basis points over the one-month bank bill swap rate on the $75 million A1 tranche of National ABS Trust 2012-1M, which has an expected weighted average life of 0.2 years.Pricing on the $295 million A2 tranche, which has a weighted average life of 1.6 years, is 150 basis points over the swap rate.Pricing on the B, C, D, E, F and G notes, which have a total value of $30 million, was not disclosed.The issue was upsized from $300 million offered at the launch. The bank said in a statement that the majority of the 12 investors were real money accounts.Medfin's customers are doctors, dentists and other medical practitioners. Almost of half the trust's asset pool is made up of motor vehicles (49 per cent), 20 per cent is medical equipment, 13 per cent is dental equipment and 17 per cent is furniture and fittings.Last month, Investec Bank (Australia) raised $232.5 million through an ABS backed with similar professional practice loans. Pricing included 65 basis points over the one-month bank bill swap rate for a tranche with a weighted average life of 0.4 years, and 165 points over the swap rate for a tranche with a weighted average life of 2.1 years.