Now don't be fooled by these renovation companies that tell you, that you don't need to have something custom made because they'll they just mix and match panel sizes until they find the size that you require, because put simply, this doesn't work all of the time. These particular companies will sell you an "off the shelf" screen and even give the number of a Glazier that will fit your screen for you and the first thing that the installer will do, is put a level on your wall and if it's out of plumb by more than 6mm that cheap screen, simply will NOT fit. So their solution then, is to have some panels custom made.
By this time it's too late to change your mind as you've already purchased the screen and although they will let you return the item, you'll find that they have a re-stocking fee of around 20% and you will also have to pay the Glazier for coming out and giving you the bad news. This virtually locks you in to proceed with what their product/s.
What this all means to you, is that you're getting a custom made screen anyway and it's going to cost you about the same as what we will sell them for, just without the hassle!