leveragedesign@aberthil I would certainly like to offer you a refund, please contact Shapeways customer service to arrange that. Can I see the picture you sent? I have not received one and would like to see the issue you're having.
leveragedesign@aberthil sorry to hear this isn't working for you, I've halted production to fix this. This cap should fit all production Garmin Quarter Turn Mounts. Which Garmin are you using?
leveragedesign@fb11bc9 Thanks for the feedback! We've updated the design to work with a deeper bolt head. Shoot us a message to get the new one for free!