There are a couple different Ameritechs out there. Where are you located?

Dallas

I made the same mistake. It is Maritech windows.

Here is a link that might be useful: Maritech Windows

Maritech is Mfg. in Carrollton, Tx. 366 Low-E is standard. Argon is Optional. Simulated Divided Lite is available. 3 colors std. Optional Painted Exterior. 450 series is Beveled face exterior. Made for New construction, but, is used in retro-fit. Warranty, Quality, Lead times & Prices are Good (as compared to locally mfg. windows). There are better Vinyl Windows out there, but, depends upon your Budget!