These cable chain mounts are made for Walpeup's Heat Bed Cable Chain for Printrbot Simple Metal to work with Printrbot.com's x axis upgrade.
I designed a new mount for the bed which uses the screws that hold the bed to the delrin bracket. I added holes for screws (m4) and a slot for a nut to the bottom mount to be able to fasten it to the printer. It needs 18 or so chain links.
I had to solder new wires onto the heat plate because they were not long enough to accommodate the length of chain.