Fits perfectly with OEM bumpers installed. Cutouts for charging and Vol/Power buttons. Print as-is without supports. May want to use a brim or at least orient the model so that its width aligns with your Y axis, if using a "bed shaker" type machine. I had no issues with adhesion though.

A version that holds a standard surface pen can be found here: https://www.thingiverse.com/thing:5716537

And a version that holds a surface slim pen can be found here: https://www.thingiverse.com/thing:5774215