Harvey manufactures this style window with stainless steel
rollers on the bottom of the sash. Most other companies call
their style of this window a slider. Sliders do just that,
slide vinyl on vinyl. Over time the two surfaces ware down
from friction thus reducing the performance of the window.
Since Harvey constructs their product with rollers, friction
never becomes an issue.
These windows add a clean look to any basement and with the
Low-E / Argon option they will also enhance your