We assign inspection team to the supplier factory, to strictly supervise raw materials and accessories from mold making to production and delivery. QC in factory will check the incoming materials once more when they arrive. Following Quality Inspection Criteria, for aluminum materials, there are standards of dimension, chromatic aberration, coating thickness, adhesion, rigidity and fluorocarbon coating. For ordinary glass, there are standards of dimension, chromatic aberration, flatness, and stress on tempered glass. For coated glass and insulated glass, we inspect the low-e films and dew point and air cavity depth respectively. For iron, stainless steel, fastener, sealant, insulating and fire-rated rock wool, we take sampling test based on international standards. Only qualified materials can be transferred to our storage.