This is a holder for a chuck it ball thrower and ball. The model is designed to use a large command strip to hold it against the wall.

Printed with 6x wall thickness, 15% infill and no supports in orientation in print profile.

Wall thickness could likely be reduced, and orientation likely could be put standing up, but may require support/the bottom surface could suffer. If you're concerned/have poor layer adhesion, it could be worth attempting to print it that way.