1/4" thick molded polyethylene. The form fitting lid minimizes evaporation built in funnel allows the tank to be easily and safely filled. Any etchant may be used, however the z*acryl tank was designed to promote the use of ferric chloride. The large tank will etch two full 18" x 24" plates, yet it uses 80% less studio space than does a traditional bath-style tray.
Instructions located here