I designed this handle to put on a cart I've been building for my workshop, to help in pulling it around. It has two holes for bolts to go through, and recessed spaces for the bolt heads to sit beneath.

I printed this in MatterHackers Build Series PLA with four wall loops, 35% infill (adaptive cubic), and it feels plenty strong for my use. Because I wanted clean holes for the bolts to thread, I printed it sitting up and with supports, rather than on its side.

You can find the file on OnShape, if you'd like to edit it yourself.