18 mm, Yes, No, Not Flame Resistant or Fire Retardant, Electrical Properties Not Tested, No.Disposable Tacky Mat with Frame, Mat Width 31 1/2 in, Mat Length 4 ft 4 in, Sheet Material Polyethylene Film, Adhesive Acrylic, Number of Sheets per Mat 60, Sheets Remaining Indicator Numbered, Overall Thickness 3.