With the Impact 500, Turtle Beach took the approach that many tenkeyless customers prefer not just a more compact keyboard, but also a more staid design. As I mentioned at the top of this article, the simplicity of the Impact 500 reminds me of the Nixeus Moda v2, with the primary difference being that the Impact 500 has its keys set into a rather deep "bowl," whereas the Moda v2 has them mounted directly on top of a backplate.
There are pros and cons to both design ideas. A bowl design is harder to clean, for sure, and it's not as striking, but the Impact 500 hides all the "business" of the switches, so the resulting visual is a sort of all-black effect. The keys are black, and so is the chassis, so the sense you get is that the Impact 500 is this solid, brick-like rectangle.
The surface of the chassis has an attractive, slightly rubberized soft-touch look. Usually, as with some of Razer's keyboards, you quickly besmudge that pretty finish with hand and finger grease, but Turtle Beach obviates this issue to an extent by keeping the surface area so minimal that there isn't much room for your grease stains to show up.
There are no additional ports on the Impact 500; the sides and back are smooth. The only aberrations are three tiny notches—one each on the left side, right side and back side—to accommodate the cable. It's a design element for which Turtle Beach should be lauded, as it's the same T-groove routing for the cable that we saw on the Nixeus Moda v2. You can route the cable directly out the back of the keyboard or run it out the left or right sides, depending on your desk setup and preferences. The only issue I see is that there isn't much clearance for the cable in the notched-out area, so if you run it left or right, I worry that there's undue stress on the connector.
The cable is detachable (it has a mini-USB connector) for better portability, and it sports a black braided design with red accents.
There are no lights on the Impact 500 save for the Caps Lock, Scroll Lock and Windows indicators. The Windows indicator light is on the F9 key, and you can activate it with Fn+F9. The other two are mounted below the PrtSc, ScrLk and Pause Break keys. All three light up in red to match the red highlights in the cable.
Turtle Beach eschewed any dedicated media buttons in favor of compactness, instead forcing some of the F keys into double duty. F5, F6, F7 and F8 offer play/pause, stop, backward and forward controls, respectively, and the F10, F11 and F12 keys give you volume controls.
I do not have full details on the key caps (per my note above explaining that Turtle Beach has not confirmed several specs). From simple observation, though, the caps are plastic with printed lettering.
The chassis is almost exactly the same width and height as the Nixeus Moda V2, although the Impact 500 is a few millimeters thicker.
(Update, 5/10/16, 8:45am PT: Fixed typo.)