These medical identification tags can be made out of stainless steel (usually classified as 316L and known as surgical stainless steel), sterling silver or gold. If found by emergency personnel the inscription provides an indication of the wearer's special medical needs. Tags are available with pre-engraved conditions or can be custom engraved with your specific medical histories and have the benefit that all information is self-contained and does not require any form of technology to view in case of an emergency.