I grabbed a set of these markers a long time ago, from some forgotten source. It turns out they're really common, and I hear all sorts of stories about places they've turned up.
All pendants come with the chain with which they are pictured. Unless otherwise noted, this chain is 16inches long, and will fall about midway between the neck and the decolletage on an average woman. We realize that measurement is a bit biased; our pendants are unisex and we are happy to provide longer chains if desired.