This model represents the Harris Refurbishment of the 1990's to extend the life of the Harris Train with Airconditioning and sealed windows. The refurbishment project was a failure, but the sets continued in service on the St. Kilda and Port Melbourne Lines as 901M-3501T-3502T-902M, 903M-3503T-3504T-904M, 905M-3505T-3506T-906M and 907M-3507T-3508T-908M.