... RoHS high quality 2.304# Stainless steel 3.Waterproof, low consumption 4,Indoor or outdoor use Stainless steel cutting metal painting letter sign ... the identification, public transport station brand etc 1) 304# stainless steel and copper metarial for choice2) face or back be ... letter signs(including backlit led sign,frontlit led sign,stainless steel sign,acrylic led sign,,crystal sign,etc),Of course ...