Dear wbgen-ctb users: I haven't mentioned this before, there is a white teflon sheet inside of the ctb. This sheet protects the bottom of the bath. Please leave it inside. Thank you, Uli -- Uli Thumser Stanford Nanofabrication Facility Center for Integrated Systems 420 Via Palou Mall, CIS Room 146 Stanford, CA 94305 (650)725-3694 uli at snf.stanford.edu