This is the top of the range in blinds. Using a splined edge which travels along a sturdy side track channel system thus stopping the fabric from ever blowing out of the track and sealing the sides off so the elements don't drift in and invade your space. Using an inner spring allowing the blind to be under tension but can be placed in any positing along the side channels. These blinds have a centre release mechanism, for easy use. This one is ideal for the homes on the beach front...