Polycarbonate Sheets Fitting Suitable for thickness: U: 4mm/6mm, 8mm/10mm, 16mm; H: 4mm/6mm, 8mm/10mm, 16mm; Advantage: Harmony to joint sheet, good after installation looking Application: To connect polycarbonate sheet and prevent dust go inside sheet. Professional accessories: PC "H"connecter, PC "U"edge, PC snap etc.