In the first mortgage-backed funding in a month, FirstMac on Friday completed a A$1 billion RMBS raising.The Australian Office of Financial Management invested $189.1 million across six tranches of the Firstmac Series 1-2020 bond."It's a very difficult market, one you would characterise as frozen until now," James Austin, CFO of FirstMac told Banking Day."This transaction is one we've been working on for the past six weeks."We had, you could call it soft commitments or verbal commitments. The emergence of the AOFM gave us the confidence to place the trade."They became firm this morning," Austin said in an interview late on Friday.Approximately 81 per cent of the transaction was placed with institutional investors across the transaction structure. Investors to the transaction participated from United Kingdom, Asia, together with domestic Australian domiciled institutions.The transaction was arranged by JP Morgan Securities Australia, along with Joint Lead Managers ANZ, NAB and Westpac.FirstMac priced the senior A-1 trance (rated AAA) at a margin of 120 basis points to the one month BBBSW rate. This is in line with the previous RMBS bond sold by the mortgage funder in late 2019 and five bps inside the pricing on the most recent deal by Columbus Capital.The twist in the deal is the pricing on the A-2 trance (also rated AAA). This was set at 75 bps over BBSW, a level Austin said was "intended to send a message to the market".The AOFM in a statement said in one tranche, the AAA rated A2 note, in which it was the sole third party investor, it priced significantly tighter than initial price guidance. "This was done to provide a buffer to the transaction that will benefit other investors and ultimately the sponsor, Firstmac, in light of the likely difficult credit conditions in the months ahead."