Version 2: less tight for top and chamber fitting. Tighter pressure against the O-ring too. This chamber was designed for the electrophoretic tissue clearing process for CLARITY. The designs were based off the dimensions found in the protocol (http://clarityresourcecenter.org/). The top thing has extensions on the inside bottom that slide down the slits on the top of the chamber thing. An o-ring can be fitted around the top of the chamber to create a seal when the top is slid down and the extensions are turned between the groove and o-ring. We use the o-ring 9557K165 from McMaster-Carr (though a smaller diameter one would probably work better). There are small holes for a wire to feed through the back, but you will probably have to drill through them to make it bigger. They are mainly used as guides. This model is still in the making. If you try it out and have any suggestions, they would be appreciated.