Polyplus Super Neutral HR-P

This type of glass is currently the generally accepted minimum standard in glass for your home. On the cavity side, this low-emissivity glass uses a fine metal coating.
The wonderful thing about this product is that the coating is virtually invisible and, as a result, it maintains the neutral nature of the glass.
The most important property of the metal coating is that it reflects the heat radiation in the home inwards and allows maximum penetration of sunlight.