DRE Vet Rodent Nose Cone/Face Masks: for Mice and RatsDescription DRE Vet Rodent Nose Cone Face Masks: for Mice and Rats Clear acrylic rodent face masks are made to fit all non rebreathing apparatuses. These masks' diaphragms seal the mask around the rodent's face, minimizing the possibility of anesthetic gases escaping into the space. Face mask diaphragms can be cut to accommodate rodents of various sizes because they are made of 12 mil thick latex. Every mask comes with additional diaphragm material.