Bite Wafers Nonlaminated Green, Extra Hard, 36/PackHygenic Bite Wafers are U-shaped, soft bite registration wax slips; designed for fast, precise impressions. Blue, foil laminated: aluminum foil laminated between 2 layers; lessens distortion and prevents patients from biting through wafer Yellow, no foil: single layer; adapts to dental arch; provides quick, precise bite-checks Green, extra hard: nonbrittle; will not shatter when chilled; softens quickly in warm water; shaped for full arch coverage