... 1, using thick aluminum alloy material, damp proof, non-deformed 2, using double-glass empty design, good sound insulation, good ... fire-proof 3,double-hollow glazing, various color 4, professional manufacturer with 20 ... 5 ,tempered double-glazing available 6 ,installed an aluminum bar inside the glass , make it damp-proof and dust-proof,;pressure-sensitive ...