| Technical specifications/Item | 
			Borosilicate Float Glass 3.3 | 
			Borosilicate Fireproof Glass 4.0 | 
		
		
			| Thickness range | 
			2mm-20mm | 
			5-12mm | 
		
		
			| Density(g/cm³) at 25℃ | 
			2.23±0.02 | 
			2.3±0.02 | 
		
		
			| Sizes | 
			1150*850mm 1700*1150mm 1830*2440mm 1950*2440mm 
			3660*2440mm ,customerized sizes are available | 
			4800*2440,customerized sizes are available | 
		
		
			| Color | 
			Ultra-clear  transmittance 92% | 
			Ultra-clear  transmittance 92% | 
		
		
			| Optical index of refraction | 
			1.48 | 
			1.47 | 
		
		
			| Coefficient of linear thermal expansion(20-300℃) | 
			3.3x10-6 K-1 | 
			4.0x10-6 K-1 | 
		
		
			| Specific heat capacity(20-100℃) | 
			0.83KJ/kg·K | 
			0.83KJ/kg·K | 
		
		
			| Thermal conductivity(90℃) | 
			1.2W/(M·K) | 
			1.2W/(M·K) | 
		
		
			| Heat short temperature | 
			240℃ | 
			300℃ | 
		
		
			| Softening point | 
			820℃ | 
			840℃ | 
		
		
			| Annealing point | 
			560℃ | 
			580℃ | 
		
		
			| Strain point | 
			510℃ | 
			530℃ |