Embossed patterned sheet often used as an antiscratch finish on London Underground vehicles by Metro-Cammell in Birmingham was produced by passing an aluminium sheet in alloy AA1200 through the rolls with a steel stencil. The stencil was returned over the top of the mill for the next sheet to be patterned. Pattern 7 was produced using a wire mesh produced by Greenings of Warrington. Pattern 2 was a "polka dot" pattern produced using a perforated steel sheet.