They were the fourth variety of BR 's then-standard NUMBER@1 design for suburban MISC@1 , eventually encompassing NUMBER@2 vehicles and five classes -LRB- NUMBER@3 / NUMBER@4 -RRB- .

They were the third variety of ORGANIZATION@1 's then-standard NUMBER@1 design for suburban MISC@1 , which eventually encompassed NUMBER@2 vehicles and five Classes -LRB- Class NUMBER@3 / NUMBER@4 -RRB- .
