Can the Kit-in Box clamp onto all desks?

The Kit-In Box can clamp on a desk as long as there is at least a 2" lip from the edge to the legs. If your tabletop is rounded, or it's glass, we don't recommend clamping. Instead the box can be placed on top of the desk.

What are the inner dimensions?

15" wide x 11" deep x 4" high. Cats like to curl up and even larger cats can fit.
The high walls are great for nesting

Does the Kit-In Box come in other stains?

No the Cherry, Mahogany, and Birch are the options available

Will the clamp scratch the desk?

The clamp comes with felt pads and rubber feet to protect your desktop.