This object is a hole plug for the chamfered corners in the bottom of the Makerbot Replicator build chamber. There is a notch to allow the wires to pass through.
This is a simple build that doesn't require a raft or a support.
You will need to build 3 to fill 3 corners. You will need to build the Replicator keypad cover to fill the 4th corner (http://www.thingiverse.com/thing:29858)
I needed to trim off some of the "post" that holds it in place for the plug that is in the back-right hand corner (it hit the cooling fan).
Their is some concern that the hole plug in the Back-Right corner might restrict air flow to the cooling fan below the build surface. I have included a picture of below the build surface (with the bottom cover removed). While some air could be brought in through that hole, there is no restriction of air as the fan is mounted about 5/8" away from the supporting wall and there is also a chamferd corner in the cover below the fan. So the fan can breath in fresh air from below the bottom cover.