The Crystal uPVC Top Opener Obscure Double Glazed Window is the most popular style in the UK.  They are characterised by outward opening vents which are combined with fixed panels (lights).  They are available in a huge range of styles and colours. The profiles are slim but strong and insulating.  When combined with high quality glazing they create a thermally efficient window which is robust and easy to maintain and will look good for years to come.

Brand Name	Crystal
Colour	White