Dreve BioBleach Hard is a clear thermoforming blank made of polyethylene, including insulation foil, for the production of stable bleaching/medication splints that end at the gingival margin. Use BioBleach Hard for: Bleach trays Situations with slight undercut areas Key Features: Slightly flexible Bonds with acrylate Transparent/Clear Pack of 25 0.5mm x 120mmø