30 mm horizontal Slider window that have some greater width than 29mm series that can be used mostly for residential. The windows open with the sash sliding left or right. Some people find a sliding glass window easier to open and close than a crank-style window. Since they slide open without protruding, horizontal sliders are an excellent choice for rooms facing walkways, porches or patios. Horizontal slider windows are a favourite for contemporary style homes and are also popular for satisfying bedroom egress requirements. In a single slider, one sash slides to open. In a double slider, both sashes open, this can be great for providing air circulation to a room