As a raw metal product they will need some form of coating on them to protect against rust spots appearing from moister in the air. A simple clear lacquer to seal them is fine which you can buy on this site in a spray can.
All painted tiles are powder coated, hand finished tiles are hand finished over a powder coated base. Painted tiles are ready for installation and don't require any additional protection.
ABOUT NAIL UP TILES
All nail up tiles are 600 x 600 mm face with a 6 mm overlap around the perimeter. Images show a single tile, some tiles have repeated patterns as part of one tile.
ABOUT DROP IN AND ACOUSTIC TILES
Drop in and Acoustic tiles are all designed for a standard metric 595 x 595 mm suspended grid.
Unfinished tiles - 2-3 weeks.
Painted tiles in a (single colour) - 3-5 weeks
Hand finished tiles (two colours) - 4-7 weeks
Drop in & Acoustic
Unfinished tiles - 2-3 weeks
Painted tiles in a (single colour) - 4-6 weeks
Hand finished tiles (two colours) - 5-7 weeks