With the standard Z-Series sill you will get performance and value.  Elements of the Z-Series sill include:

• All composite substrate: These won't crack, warp or rot, ever.
• Narrow synthetic high dam cap: This  cap resists fading and wear. It won't warp or rot. A built-in seal keeps out air and water, even in the most severe conditions.
• Sealed adjustment screws: Patented sealing plugs hide unsightly screws and keep water and dirt away from the adjustment mechanism, maintaining adjustability of the sill cap over time.

Z-Series Sills are standard on all Acclimated Entry System units, with it's composite nosing and riser available in Walnut or Oak finish.