Simulated Brass Sign Letters and Numbers are for interior use. Simulated Brass Letters have the look of brass letters, but are low cost plastic letters with a stamped foil finish and come with either a black or gold side option. The simulated letters also come in white and black. Sign Letters come with Stickee adhesive on the backs but you will need to add 100% pure silicone for secure mounting. These letters should only be used for interior signage. Letters ship in 12-15 Business Days.