We modeled the Nalgene chamber setup and designed an ETC chamber that can be 3D printed. Two sets of vertical grooves were added to hold the electrodes in place. There is also a groove for fitting an Oring. The design can be downloaded from http://www.thingiverse.com/thing:106486
. We use a Makerbot Replicator 2 and it prints well. Test units are available for those who don't have a 3D printer (yet), but only the first three requests will be honored due to our limited capacity. Please leave your request in the comments area. Thanks.