The red aluminum medical dog tags are lightweight, measuring 1 1/8" wide by 2" long. This engraved ID tag is offered with an accessory choice of either a stainless steel ball chain necklace or a spiral key ring for hooking onto a backpack or keychain! Engraving is inscribed on the back of the red medical dog tag. They are reasonably priced to cover both departments if you choose. Choose a colorful silencer to give your Medical Dog Tag a personalized look! Additional dog tag silencers are also available.