On the bridge of my Epip Sheraton II there is a wire which runs alone the part of the bridge where the screw heads for the saddle adjustments are. The wire acts like a clamp, to hold the heads in place. So that if you remove all the strings the screws with the saddles won't fall out. The bridges on my LP's don't have that. Both do have a small, tiny wire type clip between the saddle and screw head, acts like a washer, kinda. At least that's what it looks like to me.
I got this picture from the above link, from Krapsusa.