Hazel Residential PLC is an RMBS transaction securitizing a portfolio of owner-occupied (95.8%) and buy-to-let (BTL) (4.2%) mortgage loans secured against properties in the U.K. The loans in the pool are mainly legacy loans (61%) originated before 2014 by Santander UK PLC. Although the loans were originated as prime, there are some nonconforming characteristics to the pool. Santander UK PLC originated the loans in the portfolio between 1996 and 2024. It is the fourth-largest residential mortgage lender in the U.K. based on the mortgage stock. Its principal activity is retail banking, which includes residential mortgage lending. We consider Santander UK's underwriting standards to be among the best in the market. Valuations generally require a full internal inspection and there is